7Baggers

Clean Harbors, Inc
(NYSE:CLH) 

CLH stock logo

Clean Harbors, Inc. provides environmental and industrial services in North America. The company operates through two segments, Environmental Services and Safety-Kleen. The Environmental Services segment collects, transports, treats, and disposes hazardous and non-hazardous waste, such as resource r...

Founded: 1980
Full Time Employees: 14,400
Sector: Industrials
Industry: Waste Management

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Quarterly
Annual
    Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-12-31 2019-09-30 2019-06-30 2019-03-31 2018-12-31 2018-09-30 2018-06-30 2018-03-31 2017-12-31 2017-09-30 2017-06-30 2017-03-31 2016-12-31 2016-09-30 2016-06-30 2016-03-31 2015-12-31 2015-09-30 2015-06-30 2015-03-31 2014-12-31 2014-09-30 2014-06-30 2014-03-31 2013-12-31 2013-09-30 2013-06-30 2013-03-31 2012-12-31 2012-09-30 2012-06-30 2012-03-31 2011-12-31 2011-09-30 2011-06-30 2011-03-31 2010-09-30 2010-06-30 2010-03-31 2009-09-30 2009-06-30 2009-03-31 2008-09-30 2008-06-30 2008-03-31 2007-12-31 2007-09-30 2007-06-30 2007-03-31 2006-09-30 
                                                                              
      revenues:
                                                                              
      service revenues
    1,247,434,000 1,294,401,000 1,321,865,000 1,336,948,000 1,201,454,000 1,208,840,000 1,278,955,000 1,288,370,000 1,151,858,000 1,108,003,000 1,129,216,000 1,159,090,000 1,032,270,000 1,073,810,000 1,085,043,000 942,061,000 906,199,000 744,549,000 734,563,000 662,708,000 685,572,000 681,306,000 637,839,000 719,867,000 731,219,000 739,919,000 715,085,000 656,658,000 707,558,000 685,183,000 696,779,000 619,719,000 615,144,000 612,352,000 610,940,000 560,214,000 571,791,000 594,225,000 584,562,000 530,231,000 585,928,000 760,667,000 801,347,000 596,330,000 677,725,000 657,221,000 665,275,000 660,095,000 680,678,000 702,033,000 673,872,000 672,622,000                       
      product revenues
    212,103,000 205,295,000 227,472,000 212,906,000 230,496,000 222,276,000 250,467,000 264,349,000 224,837,000 230,166,000 236,480,000 238,810,000 245,828,000 289,276,000 271,269,000 227,048,000 213,282,000 206,930,000 191,895,000 145,440,000 110,618,000 98,038,000 72,161,000 138,696,000 139,786,000 151,749,000 153,593,000 124,181,000 150,646,000 157,998,000 152,361,000 130,059,000 132,259,000 143,494,000 141,848,000 128,727,000 120,322,000 135,295,000 112,948,000 105,852,000 127,116,000 132,699,000 134,881,000 136,169,000 167,299,000 194,244,000 193,205,000 186,572,000 198,752,000 205,502,000 186,656,000 189,541,000                       
      total revenues
    1,459,537,000 1,499,696,000 1,549,337,000 1,549,854,000 1,431,950,000 1,431,116,000 1,529,422,000 1,552,719,000 1,376,695,000 1,338,169,000 1,365,696,000 1,397,900,000 1,278,098,000 1,363,086,000 1,356,312,000 1,169,109,000 1,119,481,000 951,479,000 926,458,000 808,148,000 796,190,000 779,344,000 710,000,000 858,563,000 871,005,000 891,668,000 868,678,000 780,839,000 858,204,000 843,181,000 849,140,000 749,778,000 747,403,000 755,846,000 752,788,000 688,941,000 692,113,000 729,520,000 697,510,000 636,083,000 713,044,000 893,366,000 936,228,000 732,499,000 845,024,000 851,465,000 858,480,000 846,667,000 879,430,000 907,535,000 860,528,000 862,163,000                       
      yoy
    1.93% 4.79% 1.30% -0.18% 4.01% 6.95% 11.99% 11.08% 7.71% -1.83% 0.69% 19.57% 14.17% 43.26% 46.40% 44.67% 40.60% 22.09% 30.49% -5.87% -8.59% -12.60% -18.27% 9.95% 1.49% 5.75% 2.30% 4.14% 14.82% 11.55% 12.80% 8.83% 7.99% 3.61% 7.93% 8.31% -2.94% -18.34% -25.50% -13.16% -15.62% 4.92% 9.06% -13.48% -3.91% -6.18% -0.24% -1.80%                           
      qoq
    -2.68% -3.20% -0.03% 8.23% 0.06% -6.43% -1.50% 12.79% 2.88% -2.02% -2.30% 9.37% -6.23% 0.50% 16.01% 4.43% 17.66% 2.70% 14.64% 1.50% 2.16% 9.77% -17.30% -1.43% -2.32% 2.65% 11.25% -9.01% 1.78% -0.70% 13.25% 0.32% -1.12% 0.41% 9.27% -0.46% -5.13% 4.59% 9.66% -10.79% -20.18% -4.58% 27.81% -13.32% -0.76% -0.82% 1.40% -3.73% -3.10% 5.46% -0.19%                        
      cost of revenues:
                                                                              
      total cost of revenues
    1,014,120,000 1,040,728,000 1,048,490,000 1,033,497,000 1,021,884,000 1,003,502,000 1,055,599,000 1,035,542,000 971,070,000 923,147,000 943,951,000 947,512,000 891,424,000 910,648,000 898,469,000 843,389,000 792,183,000 639,232,000 617,886,000 560,536,000 548,775,000 511,629,000 470,681,000 606,666,000 615,768,000 612,754,000 594,933,000 564,364,000 594,857,000 580,685,000 583,584,000 546,425,000 526,690,000 519,595,000 519,803,000 496,585,000 496,661,000 491,915,000 480,002,000 464,279,000 522,965,000 634,646,000 652,688,000 546,507,000 610,720,000 598,407,000 606,950,000 625,719,000 645,164,000 647,119,000 614,326,000 636,024,000                       
      selling, general and administrative expenses
    207,141,000 193,894,000 189,610,000 186,183,000 182,847,000 182,039,000 177,846,000 197,876,000 181,868,000 166,007,000 171,019,000 167,382,000 168,899,000 151,711,000 155,608,000 151,173,000 159,051,000 133,164,000 124,106,000 121,641,000 111,354,000 106,544,000 103,839,000 129,307,000 123,021,000 122,301,000 123,920,000 114,812,000 141,445,000 121,219,000 125,995,000 115,088,000 118,881,000 113,252,000 112,294,000 112,221,000 99,514,000 110,954,000 107,063,000 104,484,000 92,918,000 93,113,000 120,418,000 107,715,000 103,527,000 99,701,000 115,731,000 118,962,000 104,931,000 114,464,000 122,612,000 128,470,000 75,628,000 60,339,000 66,794,000 70,759,000 75,385,000 65,704,000 58,254,000 54,794,000 53,619,000 50,729,000 45,484,000 46,416,000 37,778,000 37,369,000 40,738,000 43,496,000 39,170,000   38,196,000 31,355,000 26,880,000 
      accretion of environmental liabilities
    3,542,000 3,616,000 3,499,000 3,591,000 3,620,000 3,317,000 3,618,000 3,304,000 3,217,000 3,386,000 3,388,000 3,486,000 3,344,000 3,246,000 3,197,000 3,156,000 3,120,000 2,799,000 2,873,000 2,953,000 2,902,000 2,822,000 2,766,000 2,561,000 2,512,000 2,490,000 2,560,000 2,574,000 2,478,000 2,450,000 2,448,000 2,430,000 2,407,000 2,347,000 2,416,000 2,290,000 2,648,000 2,476,000 2,548,000 2,505,000 2,607,000 2,577,000 2,599,000 2,619,000 2,637,000 2,642,000 2,609,000 2,724,000 2,913,000 2,914,000 2,879,000 2,835,000 2,508,000 2,488,000 2,505,000 2,416,000 2,449,000 2,435,000 2,407,000 2,389,000 2,495,000 2,602,000 2,702,000 2,644,000 2,634,000 2,650,000 2,682,000 2,726,000 2,670,000 1,935,750 2,715,000 2,554,000 2,474,000 2,580,000 
      depreciation and amortization
    115,799,000 103,012,000 114,729,000 116,285,000 111,980,000 105,290,000 100,063,000 100,504,000 95,065,000 98,336,000 92,970,000 89,697,000 87,034,000 88,394,000 87,868,000 84,298,000 82,929,000 71,451,000 71,592,000 72,163,000 71,418,000 74,470,000 72,494,000 74,533,000 77,397,000 73,756,000 74,217,000 75,355,000 77,939,000 73,082,000 72,760,000 74,844,000 71,490,000 72,989,000 71,531,000 72,412,000 71,347,000 73,360,000 73,393,000 68,902,000 69,005,000 69,060,000 67,773,000 68,356,000 70,603,000 70,049,000 66,075,000 69,356,000 67,545,000 69,430,000 67,468,000 60,006,000 44,852,000 41,300,000 38,663,000 36,831,000 35,663,000 34,604,000 26,936,000 25,460,000 22,892,000 22,105,000 22,674,000 18,649,000 12,241,000 12,061,000 11,414,000 10,806,000 10,475,000 6,950,250 9,814,000 9,049,000 8,938,000 11,063,000 
      income from operations
    118,935,000 158,446,000 193,009,000 210,298,000 111,619,000 136,968,000 192,296,000 215,493,000 125,475,000 147,293,000 154,368,000 189,823,000 127,397,000 209,087,000 211,170,000 87,093,000 82,198,000 104,833,000 110,001,000 50,855,000 61,741,000 83,879,000 60,220,000 45,496,000 52,307,000 80,367,000 73,048,000 23,734,000 41,485,000 65,745,000 64,353,000 10,991,000 27,935,000 47,663,000 46,744,000 5,433,000 21,943,000 16,802,000 34,504,000 -4,087,000 25,549,000 93,970,000 60,758,000 7,302,000 57,537,000 -42,748,000 67,115,000 29,906,000 58,877,000 73,608,000 53,243,000 34,828,000 36,231,000 56,739,000 47,533,000 61,701,000 59,247,000 66,792,000 51,884,000 39,742,000 73,372,000 71,923,000 23,619,000 26,999,000 16,430,000 10,713,000 31,260,000 29,847,000 20,000,000 15,039,750 25,879,000 23,627,000 10,653,000 21,774,000 
      yoy
    6.55% 15.68% 0.37% -2.41% -11.04% -7.01% 24.57% 13.52% -1.51% -29.55% -26.90% 117.95% 54.99% 99.45% 91.97% 71.26% 33.13% 24.98% 82.67% 11.78% 18.04% 4.37% -17.56% 91.69% 26.09% 22.24% 13.51% 115.94% 48.51% 37.94% 37.67% 102.30% 27.31% 183.67% 35.47% -232.93% -14.11% -82.12% -43.21% -155.97% -55.60% -319.82% -9.47% -75.58% -2.28% -158.08% 26.05% -14.13% 62.50% 29.73% 12.01% -43.55% -38.85% -15.05% -8.39% 55.25% -19.25% -7.13% 119.67% 47.20% 346.57% 571.36% -24.44% -9.54% -17.85% -28.77% 20.79% 26.33% 87.74% -30.93%     
      qoq
    -24.94% -17.91% -8.22% 88.41% -18.51% -28.77% -10.76% 71.74% -14.81% -4.58% -18.68% 49.00% -39.07% -0.99% 142.46% 5.96% -21.59% -4.70% 116.30% -17.63% -26.39% 39.29% 32.36% -13.02% -34.91% 10.02% 207.78% -42.79% -36.90% 2.16% 485.51% -60.66% -41.39% 1.97% 760.37% -75.24% 30.60% -51.30% -944.24% -116.00% -72.81% 54.66% 732.07% -87.31% -234.60% -163.69% 124.42% -49.21% -20.01% 38.25% 52.87% -3.87% -36.14% 19.37% -22.96% 4.14% -11.30% 28.73% 30.55% -45.83% 2.01% 204.51% -12.52% 64.33% 53.37% -65.73% 4.73% 49.24% 32.98% -41.88% 9.53% 121.79% -51.07%  
      operating margin %
    8.15% 10.57% 12.46% 13.57% 7.79% 9.57% 12.57% 13.88% 9.11% 11.01% 11.30% 13.58% 9.97% 15.34% 15.57% 7.45% 7.34% 11.02% 11.87% 6.29% 7.75% 10.76% 8.48% 5.30% 6.01% 9.01% 8.41% 3.04% 4.83% 7.80% 7.58% 1.47% 3.74% 6.31% 6.21% 0.79% 3.17% 2.30% 4.95% -0.64% 3.58% 10.52% 6.49% 1.00% 6.81% -5.02% 7.82% 3.53% 6.69% 8.11% 6.19% 4.04% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% 
      other expense
    -731,000   -603,000 -932,000   -167,000           -1,480,000 -1,228,000         -112,250 -996,000  -299,000 -703,500 -432,000 -833,000 -1,549,000 -184,250 -198,000                                     
      interest expense, net of interest income of 6,413 and 5,628, respectively
    -33,854,000                                                                          
      income before provision for income taxes
    84,350,000 119,942,000 160,826,000 172,589,000 74,610,000 103,377,000 155,394,000 178,877,000 95,795,000 121,728,000 125,006,000  99,065,000 181,110,000 195,043,000 62,780,000 60,488,000 87,048,000 90,470,000 31,709,000 43,776,000 68,622,000 40,882,000 21,270,000 34,898,000 54,119,000 52,269,000 6,953,000 17,266,000 42,364,000 44,430,000 -9,578,000 3,652,000 24,633,000 49,096,000 -18,692,000 7,995,000 11,470,000       38,543,000 -61,629,000  14,530,000                           
      provision for income taxes
    21,149,000 33,352,000 42,027,000 45,684,000 15,930,000 19,403,000 40,181,000 45,597,000 25,963,000 23,379,000 33,666,000  16,591,000 45,311,000 46,886,000 17,466,000 11,495,000 21,605,000 23,395,000 9,973,000 4,444,000 13,712,000 11,859,000 9,698,000 10,747,000 17,750,000 16,025,000 5,977,000 835,000 11,275,000 13,683,000 3,053,000 -80,542,000 12,575,000 23,216,000 2,701,000 20,708,000 21,725,000       11,166,000 31,708,000  5,570,000                           
      net income
    63,201,000 86,590,000 118,799,000 126,905,000 58,680,000 83,974,000 115,213,000 133,280,000 69,832,000 98,349,000 91,340,000 115,766,000 82,474,000 135,799,000 148,157,000 45,314,000 48,993,000 65,443,000 67,075,000 21,736,000 39,332,000 54,910,000 29,023,000 11,572,000 24,151,000 36,369,000 36,244,000 976,000 16,431,000 31,089,000 30,747,000 -12,631,000 84,194,000 12,058,000 25,880,000 -21,393,000 -12,713,000 -10,255,000 3,966,000 -20,871,000 568,000 40,228,000 10,395,000 -7,089,000 27,377,000 -93,337,000 28,672,000 8,960,000 26,801,000 35,361,000 22,902,000 10,502,000 61,874,000 12,359,000 23,426,000 32,015,000 38,233,000 37,133,000 29,156,000 22,730,000 38,827,000 57,929,000 10,430,000 9,185,000 8,624,000 4,955,000 14,628,000 15,987,000 8,922,000 6,907,250 12,940,000 11,188,000 3,501,000 21,005,000 
      yoy
    7.70% 3.12% 3.11% -4.78% -15.97% -14.62% 26.14% 15.13% -15.33% -27.58% -38.35% 155.48% 68.34% 107.51% 120.88% 108.47% 24.56% 19.18% 131.11% 87.83% 62.86% 50.98% -19.92% 1085.66% 46.98% 16.98% 17.88% -107.73% -80.48% 157.83% 18.81% -40.96% -762.27% -217.58% 552.55% 2.50% -2338.20% -125.49% -61.85% 194.41% -97.93% -143.10% -63.75% -179.12% 2.15% -363.95% 25.19% -14.68% -56.68% 186.12% -2.24% -67.20% 61.83% -66.72% -19.65% 40.85% -1.53% -35.90% 179.54% 147.47% 350.22% 1069.10% -28.70% -42.55% -3.34% -28.26% 13.04% 42.89% 154.84% -67.12%     
      qoq
    -27.01% -27.11% -6.39% 116.27% -30.12% -27.11% -13.56% 90.86% -29.00% 7.67% -21.10% 40.37% -39.27% -8.34% 226.96% -7.51% -25.14% -2.43% 208.59% -44.74% -28.37% 89.19% 150.80% -52.08% -33.59% 0.34% 3613.52% -94.06% -47.15% 1.11% -343.42% -115.00% 598.24% -53.41% -220.97% 68.28% 23.97% -358.57% -119.00% -3774.47% -98.59% 286.99% -246.64% -125.89% -129.33% -425.53% 220.00% -66.57% -24.21% 54.40% 118.07% -83.03% 400.64% -47.24% -26.83% -16.26% 2.96% 27.36% 28.27% -41.46% -32.97% 455.41% 13.55% 6.51% 74.05% -66.13% -8.50% 79.19% 29.17% -46.62% 15.66% 219.57% -83.33%  
      net income margin %
    4.33% 5.77% 7.67% 8.19% 4.10% 5.87% 7.53% 8.58% 5.07% 7.35% 6.69% 8.28% 6.45% 9.96% 10.92% 3.88% 4.38% 6.88% 7.24% 2.69% 4.94% 7.05% 4.09% 1.35% 2.77% 4.08% 4.17% 0.12% 1.91% 3.69% 3.62% -1.68% 11.26% 1.60% 3.44% -3.11% -1.84% -1.41% 0.57% -3.28% 0.08% 4.50% 1.11% -0.97% 3.24% -10.96% 3.34% 1.06% 3.05% 3.90% 2.66% 1.22% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% Infinity% 
      earnings per share:
                                                                              
      basic
    1.2 1.64 2.22 2.37 1.09 1.56 2.14 2.47 1.29 1.82 1.69 2.14 1.52 2.51 2.73 0.83 0.9 1.2 1.23 0.4 0.71 0.99 0.52 0.21 0.43 0.65 0.65 0.02 0.29 0.55 0.55  1.48 0.21 0.45  -0.22 -0.18 0.07  0.02 0.69 0.18 -0.12 0.45 -1.55 0.47 0.15 0.44 0.58 0.38 0.17 1.14 0.23 0.44 0.6 0.72 0.7 0.55 0.86 1.47 2.2 0.4 0.36 0.36 0.21         
      diluted
    1.19 1.63 2.21 2.36 1.09 1.55 2.12 2.46 1.29 1.81 1.68 2.13 1.52 2.5 2.71 0.83 0.9 1.2 1.22 0.39 0.71 0.99 0.52 0.21 0.43 0.65 0.65 0.02 0.29 0.55 0.54  1.47 0.21 0.45  -0.22 -0.18 0.07  0.02 0.69 0.18 -0.12 0.45 -1.55 0.47 0.15 0.44 0.58 0.38 0.17 1.13 0.23 0.44 0.6 0.72 0.7 0.55 0.86 1.47 2.19 0.4 0.36 0.36 0.21         
      shares used to compute earnings per share - basic
    52,821 13,414.75 53,518 53,593 53,759 13,484 53,951 53,932 53,930 13,524.25 54,122 54,092 13,569.5 54,111 54,318 54,408 13,638.25 54,411 54,529 54,723 13,911.5 55,592 55,590 55,757 13,964.5 55,850 55,875 55,848 14,055.5 56,059 56,410  14,287.25 57,033 57,190  14,393.75 57,487 57,549  14,699.75 58,161 58,590 58,875 15,146.25 60,369 60,665 60,720                           
      shares used to compute earnings per share - diluted
    52,992 13,467.75 53,713 53,799 53,993 13,557.25 54,229 54,248 54,213 13,602.75 54,419 54,448 13,635.5 54,381 54,597 54,672 13,715.5 54,707 54,854 55,043 13,958 55,738 55,748 56,055 14,027.25 56,165 56,066 56,082 14,090 56,291 56,505  14,320 57,195 57,336  14,393.75 57,487 57,678  14,724.5 58,268 58,710 58,875 15,146.25 60,369 60,778 60,861                           
      other income
     3,218,000 3,517,000   977,000 -1,123,000  -1,141,000 3,148,000 334,000 -1,283,000 399,000 104,000 1,265,000 704,000 1,994,000 199,000   307,000 2,268,000 -500,000 -2,365,000 905,000 -427,000 -564,000 2,983,000   846,000        -189,000 -350,000 -990,000 -139,000 -660,000 409,000 244,000 613,000 -655,000 4,178,000 -325,000 -150,000 1,655,000 525,000 -337,000 -91,000 -75,000 -299,000 471,000 164,000 2,868,000 2,899,000  2,708,000 446,000 111,000 11,000 33,000  59,000  15,500 61,000  6,000  
      interest expense, net of interest income of 6,497, 5,391, 17,212 and 13,257, respectively
     -27,220,750 -35,700,000                                                                        
      interest expense, net of interest income of 5,086, 4,352, 10,714 and 7,866, respectively
       -37,106,000                                                                       
      interest expense, net of interest income of 5,628 and 3,514, respectively
        -36,077,000                                                                      
      loss on early extinguishment of debt
             -518,000               -12,000 -6,119,000   -19,000 -2,469,000    -1,846,000 -6,045,000                   -26,385,000                     
      interest expense, net of interest income of 5,391, 2,877, 13,257, and 7,833, respectively
         -25,191,750 -35,779,000                                                                    
      interest expense, net of interest income of 4,352, 2,001, 7,866, and 4,956, respectively
           -36,449,000                                                                   
      interest expense, net of interest income of 3,514 and 2,955, respectively
            -28,539,000                                                                  
      gain on sale of business
                2,216,000  8,864,000                    31,722,000  453,000 16,431,000                                     
      interest expense, net of interest income of 2,877, 1,103, 7,833 and 2,159, respectively
             -20,100,000 -29,696,000                                                                
      interest expense, net of interest income of 2,001, 563, 4,956 and 1,056, respectively
               -30,072,000                                                               
      income before benefit from income taxes
               158,468,000                           12,668,000  5,710,000 74,814,000 40,849,000    47,078,000  26,231,250 54,132,000 35,313,000 15,480,000 26,321,750 18,667,000 36,490,000 50,130,000         14,832,000 9,366,000 25,016,000 27,391,000 16,511,000   19,927,000 7,475,000  
      benefit from income taxes
               42,702,000                           8,702,000  5,142,000 34,586,000 30,454,000    18,406,000  9,040,000 18,771,000 12,411,000 4,978,000 9,371,750 6,308,000 13,064,000 18,115,000 10,143,000 18,896,000 14,954,000 13,433,000 24,384,000 11,468,000 7,089,000 6,928,000 6,208,000 4,411,000 10,388,000 11,404,000 7,589,000 5,672,750 9,978,000 8,739,000 3,974,000  
      interest expense, net of interest income of 1,103, 653, 2,159 and 1,712, respectively
                -19,838,500 -28,081,000                                                             
      interest expense, net of interest income of 563, 580, 1,056 and 1,060, respectively
                  -26,256,000                                                            
      interest expense, net of interest income of 493 and 479, respectively
                   -25,017,000                                                           
      loss on sale of businesses
                        -844,000 -118,000 -184,000 -3,074,000                                                   
      interest expense, net of interest income of 653, 1,236, 1,712 and 2,902, respectively
                    -13,488,250 -17,984,000                                                         
      interest expense, net of interest income of 580, 668, 1,060 and 1,666, respectively
                      -18,051,000                                                        
      interest expense, net of interest income of 479 and 998, respectively
                       -17,918,000                                                       
      interest expense, net of interest income of 1,236, 1,152, 2,902 and 2,981, respectively
                        -13,712,000 -17,407,000                                                     
      interest expense, net of interest income of 668, 903, 1,666 and 1,829, respectively
                          -18,654,000                                                    
      interest expense, net of interest income of 998 and 926, respectively
                           -18,787,000                                                   
      interest expense, net of interest income of 1,152, 736, 2,981 and 2,086, respectively
                            -14,920,250 -19,702,000                                                 
      interest expense, net of interest income of 903, 587, 1,829 and 1,350, respectively
                              -20,215,000                                                
      interest expense, net of interest income of 926 and 764, respectively
                               -19,764,000                                               
      interest expense, net of interest income of 736, 573, 2,086 and 1,098, respectively
                                -15,238,750 -19,916,000                                             
      interest expense, net of interest income of 587, 311, 1,350 and 520, respectively
                                  -20,769,000                                            
      interest expense, net of interest income of 764 and 215, respectively
                                   -20,270,000                                           
      loss per share:
                                                                              
      basic
                                   -0.22    -0.37    -0.36                                   
      diluted
                                   -0.22    -0.37    -0.36                                   
      shares used to compute loss per share - basic
                                   56,457    57,262    57,617                                   
      shares used to compute loss per share - diluted
                                   56,457    57,262    57,617                                   
      cost of revenues
                                                        399,743,000 372,940,000 367,623,000 400,315,000 373,142,000 386,518,000 307,754,000 312,577,000 335,273,000 324,280,000 260,417,000 210,900,000 146,254,000 143,513,000 187,063,000 178,384,000 170,194,000 121,473,250 169,007,000 165,282,000 151,604,000 151,606,000 
      goodwill impairment charge
                                        8,503,250 34,013,000     31,992,000   123,414,000                             
      gain on sale of businesses
                                    -913,000 -77,000                                         
      interest expense, net of interest income of 573, 196, 1,098 and 571, respectively
                                    -16,435,750 -20,675,000                                         
      interest expense, net of interest income of 311, 225, 520 and 375, respectively
                                      -22,492,000                                        
      interest expense, net of interest income of 215 and 150, respectively
                                       -22,576,000                                       
      interest expense, net of interest income of 196, 126, 571 and 465, respectively
                                        -15,548,000 -21,565,000                                     
      interest expense, net of interest income of 225, 188, 375 and 339, respectively
                                          -21,647,000                                    
      interest expense, net of interest income of 150 and 151, respectively
                                           -18,980,000                                   
      income before benefit for income taxes
                                           -23,417,000    -11,727,000                               
      benefit for income taxes
                                           -2,546,000    -4,638,000                               
      interest expense, net of interest income of 126, 174, 465 and 590, respectively
                                            -14,426,000 -19,017,000                                 
      interest expense, net of interest income of 188, 211, 339 and 416, respectively
                                              -19,249,000                                
      interest expense, net of interest income of 151 and 205, respectively
                                               -19,438,000                               
      interest expense, net of interest income of 174, 96, 590 and 362, respectively
                                                -14,607,500 -19,494,000                             
      interest expense, net of interest income of 211, 155, 416 and 266, respectively
                                                  -19,382,000                            
      interest expense, net of interest income of 205 and 111, respectively
                                                   -19,554,000                           
      interest expense, net of interest income of 96 and 362 for the quarter and year-to-date ended 2013 and 221 and 623 for the quarter and year-to-date ended 2012, respectively
                                                    -14,696,000 -19,326,000                         
      weighted-average common shares outstanding - basic
                                                     60,610 60,550 60,464  53,374                     
      weighted-average common shares outstanding - diluted
                                                     60,760 60,687 60,630  53,565                     
      interest expense, net of interest income of 155 and 266 for the quarter and year-to-date ended 2013 and 215 and 402 for the quarter and year-to-date ended 2012, respectively
                                                      -19,585,000                        
      interest expense, net of interest income of 111 and 186, respectively
                                                       -19,873,000                       
      revenues
                                                        558,962,000 533,806,000 523,118,000 572,022,000 545,886,000 556,053,000 447,235,000 434,962,000 487,651,000 471,639,000 354,896,000 305,608,000 215,337,000 206,306,000 273,157,000 265,259,000 242,509,000 172,309,750 245,507,000 238,708,000 205,024,000 213,903,000 
      interest expense, net of interest income of 221 and 623 for the quarter and year-to-date ended 2012 and 153 and 700 for the quarter and year-to-date ended 2011, respectively
                                                        -8,459,000 -11,596,000                     
      interest expense, net of interest income of 215 and 402 for the quarter and year-to-date ended 2012 and 302 and 546 for the quarter and year-to-date ended 2011, respectively
                                                          -10,968,000                    
      weighted-average common shares outstanding
                                                        53,884  53,308 53,227 52,961 53,023 52,939 26,399 26,329 26,291 26,251 25,420 23,777 23,748 23,423 22,437 20,357  19,840 19,817 19,750 19,587 
      weighted-average common shares outstanding plus potentially dilutive common shares
                                                        54,079  53,505 53,488 53,324 53,370 53,362 26,579 26,485 26,425 26,371 25,552 23,889 23,862 23,822 22,936 20,910  20,686 20,661 20,637 20,607 
      interest expense, net of interest income of 186 and 244, respectively
                                                           -11,272,000                   
      interest expense, net of interest income of 153 and 700 for the quarter and year-to-date ended 2011 and 297 and 564 for the quarter and year-to-date ended 2010, respectively
                                                            -7,011,750 -10,927,000                 
      income from continuing operations before benefit from income taxes
                                                            48,376,000 56,029,000  36,163,000   17,137,000 15,701,000           
      income from continuing operations
                                                            38,233,000 37,133,000 29,156,000 22,730,000 38,827,000 55,517,000 10,048,000 8,773,000           
      income from discontinued operations, net of tax
                                                                 2,412,000 382,000 412,000           
      interest expense, net of interest income of 302 and 546 for the quarter and year-to-date ended 2011 and 165 and 267 for the quarter and year-to-date ended 2010, respectively
                                                                              
      income from continuing operations, before benefit from income taxes
                                                              44,110,000  63,211,000 66,985,000             
      interest expense, net of interest income of 244 and 102, respectively
                                                                              
      interest expense, net of interest income of 297 and 564 for the quarter and year-to-date ended 2010 and 265 and 888 for the quarter and year-to-date ended 2009, respectively
                                                                              
      interest expense, net of interest income of 165 and 267 for the quarter and year-to-date ending 2010 and 233 and 623 for the quarter and year-to-date ending 2009, respectively
                                                                              
      interest expense, net of interest income of 102 and 390, respectively
                                                                              
      interest expense, net of interest income of 265 and 888 for the quarter and year-to-date ending 2009 and 1,458 and 3,952 for the quarter and year-to-date ending 2008, respectively
                                                                              
      interest expense, net of interest income of 233 and 623 for the quarter and year-to-date ending 2009 and 1,431 and 2,493 for the quarter and year-to-date ending 2008, respectively
                                                                              
      interest (expense), net of interest income of 390 and 1,062, respectively
                                                                              
      interest (expense), net of interest income of 1,458 and 3,952 for the quarter and year-to-date ending 2008 and 1,166 and 2,713 for the quarter and year-to-date ending 2007, respectively
                                                                              
      dividends on series b preferred stock
                                                                         51,500 69,000 69,000 69,000 69,000 
      net income attributable to common stockholders
                                                                      14,628,000 15,987,000 8,922,000 6,855,750 12,871,000 11,119,000 3,432,000 20,936,000 
      earnings per share:
                                                                              
      basic income attributable to common stockholders
                                                                      0.62 0.71 0.44 0.348 0.65 0.56 0.17 1.07 
      diluted income attributable to common stockholders
                                                                      0.61 0.7 0.43 0.333 0.63 0.54 0.17 1.02 
      interest (expense), net of interest income of 1,431 and 2,493 for the quarter and year-to-date ending 2008 and 753 and 1,548 for the quarter and year-to-date ending 2007, respectively
                                                                              
      interest (expense), net of interest income of 1,062 and 795, respectively
                                                                              
      selling, general and administrative
                                                                         26,910,750 38,092,000    
      interest income
                                                                         678,250 1,166,000    
      interest expense
                                                                              
      income before benefit from income taxes and equity interest in joint venture
                                                                         12,580,000 22,918,000   18,409,000 
      equity interest in joint venture
                                                                              
      interest (expense), net of interest income of 753 and 1,548 for the quarter and year-to-date ending 2007 and 1,006 and 1,775 for the quarter and year-to-date ending 2006, respectively
                                                                              
      interest (expense), net of interest income of 795 and 769, respectively
                                                                              
      interest (expense), net of interest income of 953 and 2,727 for the quarter and year-to-date ending 2006 and 266 and 752 for the quarter and year-to-date ending 2005, respectively
                                                                              
    Balance Sheets:
    Quarterly
    Annual
      Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-12-31 2019-09-30 2019-06-30 2019-03-31 2018-12-31 2018-09-30 2018-06-30 2018-03-31 2017-12-31 2017-09-30 2017-06-30 2017-03-31 2016-12-31 2016-09-30 2016-06-30 2016-03-31 2015-12-31 2015-09-30 2015-06-30 2015-03-31 2014-12-31 2014-09-30 2014-06-30 2014-03-31 2013-12-31 2013-09-30 2013-06-30 2013-03-31 2012-12-31 2012-09-30 2012-06-30 2012-03-31 2011-12-31 2011-09-30 2011-06-30 2011-03-31 2010-09-30 2010-06-30 2010-03-31 2009-09-30 2009-06-30 2009-03-31 2008-09-30 2008-06-30 2008-03-31 2007-09-30 2007-06-30 2007-03-31 2006-09-30 
                                                                               
        assets
                                                                               
        current assets:
                                                                               
        cash and cash equivalents
      547,994,000 826,315,000 759,197,000 600,186,000 489,417,000 687,192,000 512,371,000 401,992,000 337,825,000 444,698,000 335,965,000 238,776,000 492,603,000 449,023,000 344,631,000 339,584,000 452,575,000 646,663,000 595,574,000 496,383,000 519,101,000 475,706,000 447,366,000 432,205,000 371,991,000 282,233,000 204,455,000 167,371,000 226,507,000 215,497,000 197,068,000 186,352,000 319,399,000 361,658,000 446,366,000 297,366,000 306,997,000 257,857,000 352,923,000 355,345,000 184,708,000 179,191,000 173,621,000 233,739,000 246,879,000 258,021,000 278,644,000 249,007,000 310,073,000 248,635,000 263,478,000 222,104,000 229,836,000 523,614,000 296,758,000 241,527,000 260,723,000 257,159,000 377,576,000 531,763,000 280,916,000 295,300,000 206,604,000 220,276,000 255,407,000 226,961,000 252,959,000 281,893,000 86,153,000 91,856,000 77,356,000 57,948,000 72,890,000 
        short-term marketable securities
      121,040,000 127,363,000 91,176,000 98,888,000 105,895,000 102,634,000 82,371,000 91,294,000 104,811,000 106,101,000 84,007,000 87,346,000 62,033,000 65,034,000 70,797,000 75,364,000 81,724,000 64,844,000 70,683,000 74,320,000 51,857,000 56,639,000 59,326,000 62,143,000 42,421,000 46,877,000 55,198,000 57,477,000 52,856,000 37,380,000 36,862,000 37,792,000 38,179,000                                         
        accounts receivable
      1,113,163,000 1,044,137,000 1,104,805,000 1,117,714,000 1,077,510,000 1,015,357,000 1,100,660,000 1,089,832,000 1,039,763,000 983,111,000 1,010,335,000 981,233,000 964,603,000 1,026,226,000 1,005,488,000 900,273,000 792,734,000 703,199,000 659,364,000 620,184,000 611,534,000 602,069,000 572,373,000 658,482,000 644,738,000 641,667,000 632,888,000 613,507,000 606,952,000 608,645,000 590,580,000 551,841,000 528,924,000 531,696,000 512,375,000 480,044,000 496,226,000 512,376,000 503,749,000 458,301,000 496,004,000 600,283,000 684,875,000 521,563,000 557,131,000 575,575,000 575,187,000 566,394,000 579,394,000 603,054,000 549,909,000 563,691,000 541,423,000 399,362,000 397,453,000 463,431,000 449,553,000 414,079,000 352,809,000 347,532,000 344,320,000 337,636,000 297,751,000 255,436,000 148,610,000 150,297,000 186,249,000 185,228,000 180,411,000 181,826,000 179,103,000 160,780,000 169,515,000 
        unbilled accounts receivable
      192,241,000 160,888,000 182,059,000 177,910,000 171,089,000 162,215,000 204,308,000 187,148,000 165,592,000 107,859,000 130,888,000 122,679,000 107,010,000 134,742,000 134,173,000 123,945,000 94,963,000 69,912,000 59,446,000 55,239,000 55,681,000 59,438,000 44,761,000 51,215,000 56,326,000 58,842,000 52,174,000 42,513,000 54,794,000 63,964,000 62,762,000 63,375,000 35,922,000 40,933,000 46,576,000 28,106,000 36,190,000 41,542,000 29,119,000 31,805,000 25,940,000 41,562,000 37,095,000 33,333,000 40,775,000 50,050,000 35,529,000 40,832,000 26,568,000 42,122,000 34,277,000 32,220,000 27,072,000 34,401,000 30,173,000 29,904,000 29,385,000 41,728,000 30,588,000 16,891,000 26,162,000 31,951,000 21,057,000 20,198,000 6,381,000 6,385,000 10,469,000 10,235,000 15,051,000 25,229,000 20,010,000 15,364,000 16,828,000 
        inventories and supplies
      363,935,000 372,088,000 377,308,000 383,351,000 376,024,000 384,657,000 376,564,000 365,356,000 354,310,000 327,511,000 311,512,000 325,882,000 324,994,000 294,220,000 275,696,000 264,733,000 250,692,000 228,682,000 215,725,000 219,499,000 220,498,000 220,884,000 219,808,000 216,532,000 214,744,000 210,827,000 203,331,000 200,814,000 199,479,000 196,045,000 193,544,000 181,438,000 176,012,000 173,097,000 172,540,000 182,038,000 178,428,000 177,288,000 162,404,000 154,768,000 149,521,000 150,255,000 149,861,000 143,052,000 168,663,000 170,934,000 161,792,000 152,443,000 152,096,000 155,301,000 155,538,000 144,476,000 171,441,000                     
        prepaid expenses and other current assets
      104,759,000 116,452,000 93,716,000 97,332,000 90,747,000 81,741,000 78,204,000 93,440,000 103,495,000 82,939,000 78,045,000 92,559,000 82,518,000 71,846,000 93,320,000 103,349,000 68,483,000 70,864,000 76,524,000 76,726,000 67,051,000 58,711,000 69,455,000 44,629,000 48,942,000 38,199,000 42,640,000 45,925,000 42,800,000 35,441,000 34,834,000 38,177,000 35,175,000 32,637,000 35,823,000 55,180,000 56,116,000 40,898,000 49,678,000 44,056,000 46,265,000 44,880,000 60,880,000 56,263,000 57,435,000 48,540,000 48,991,000 56,677,000 41,962,000 41,880,000 53,471,000 57,828,000 75,778,000 53,252,000 49,763,000 62,118,000 73,349,000 37,278,000 32,828,000 30,007,000 20,523,000 18,708,000 18,417,000 18,431,000 10,402,000 17,553,000 6,335,000 11,369,000 12,918,000 7,034,000 9,614,000 10,219,000 9,208,000 
        total current assets
      2,443,132,000 2,647,243,000 2,608,261,000 2,475,381,000 2,310,682,000 2,433,796,000 2,354,478,000 2,229,062,000 2,105,796,000 2,052,219,000 1,950,752,000 1,848,475,000 2,033,761,000 2,041,091,000 1,924,105,000 1,807,248,000 1,741,171,000 1,784,164,000 1,677,316,000 1,542,351,000 1,525,722,000 1,493,659,000 1,431,804,000 1,486,476,000 1,400,908,000 1,300,584,000 1,213,186,000 1,148,122,000 1,202,158,000 1,176,821,000 1,136,482,000 1,079,822,000 1,154,056,000 1,160,258,000 1,234,734,000 1,061,771,000 1,092,871,000 1,049,931,000 1,119,134,000 1,063,621,000 921,196,000 1,072,555,000 1,163,317,000 1,043,185,000 1,126,433,000 1,153,937,000 1,150,291,000 1,114,558,000 1,171,179,000 1,141,774,000 1,105,191,000 1,073,582,000 1,086,793,000 1,109,288,000 865,508,000 881,885,000 891,868,000 826,270,000 866,372,000 997,876,000 744,377,000 751,480,000 629,242,000 592,323,000 467,237,000 446,215,000 501,515,000 531,489,000 337,435,000 357,878,000 336,913,000 299,828,000 318,570,000 
        property, plant and equipment
      2,562,156,000 2,541,067,000 2,497,600,000 2,507,101,000 2,463,620,000 2,447,941,000 2,452,312,000 2,408,647,000 2,330,484,000 2,193,318,000 2,128,508,000 2,082,693,000 1,980,302,000 1,923,675,000 1,913,145,000 1,881,542,000 1,863,175,000 1,508,356,000 1,531,289,000 1,527,944,000 1,525,298,000 1,539,333,000 1,553,808,000 1,547,119,000 1,588,151,000 1,593,993,000 1,596,917,000 1,588,613,000 1,561,978,000 1,614,429,000 1,609,382,000 1,631,648,000 1,587,365,000 1,611,971,000 1,602,453,000 1,609,490,000 1,611,827,000 1,648,571,000 1,594,987,000 1,596,872,000 1,532,467,000 1,531,548,000 1,562,254,000 1,502,497,000 1,558,834,000 1,579,701,000 1,611,298,000 1,588,286,000 1,602,170,000 1,615,427,000 1,554,972,000 1,549,806,000 1,531,763,000                     
        other assets:
                                                                               
        operating lease right-of-use assets
      263,251,000 255,084,000 241,048,000 247,033,000 247,414,000 250,853,000 246,061,000 214,858,000 206,577,000 187,060,000 188,695,000 181,243,000 166,181,000 161,668,000 157,048,000 156,811,000 161,797,000 137,429,000 135,363,000 142,006,000 150,341,000 146,454,000 153,522,000 160,526,000 162,206,000 164,302,000 173,504,000 170,550,000                                              
        goodwill
      1,555,062,000 1,479,050,000 1,478,831,000 1,479,805,000 1,477,307,000 1,477,199,000 1,485,065,000 1,482,085,000 1,487,821,000 1,287,736,000 1,286,473,000 1,288,291,000 1,246,878,000 1,246,327,000 1,244,655,000 1,221,399,000 1,227,042,000 543,028,000 544,639,000 543,605,000 527,023,000 524,261,000 523,154,000 519,627,000 525,013,000 524,581,000 525,044,000 517,910,000 514,189,000 514,102,000 497,251,000 492,705,000 478,523,000 478,728,000 472,819,000 469,860,000 465,154,000 470,633,000 461,491,000 460,642,000 453,105,000 447,918,000 452,858,000 445,412,000 452,669,000 449,577,000 578,974,000 565,062,000 570,960,000 590,152,000 575,275,000 572,406,000 593,771,000 157,724,000 135,962,000 125,723,000 122,392,000 134,696,000 88,511,000 61,786,000 58,557,000 56,997,000 56,713,000 49,699,000 30,580,000 29,765,000 22,726,000 22,523,000 24,809,000 21,655,000 21,590,000 21,667,000 19,032,000 
        permits and other intangibles
      679,081,000 653,027,000 663,965,000 677,180,000 688,957,000 701,987,000 708,935,000 727,463,000 739,975,000 602,797,000 613,540,000 626,320,000 620,782,000 621,834,000 637,254,000 633,445,000 644,912,000 366,497,000 374,230,000 380,053,000 386,620,000 392,401,000 400,448,000 406,881,000 419,066,000 425,863,000 433,853,000 438,958,000 441,875,000 451,355,000 455,920,000 464,635,000 469,128,000 477,639,000 482,828,000 490,952,000 498,721,000 507,337,000 492,224,000 502,532,000 506,818,000 518,995,000 534,621,000 520,045,000 530,080,000 541,874,000 553,658,000 557,211,000 569,973,000 567,776,000 555,422,000 566,910,000 572,817,000 151,810,000                    
        other long-term assets
      49,884,000 48,585,000 50,594,000 53,429,000 58,407,000 65,502,000 59,159,000 74,833,000 69,170,000 59,739,000                                                                
        total other assets
      2,547,278,000 2,435,746,000 2,434,438,000 2,457,447,000 2,472,085,000 2,495,541,000 2,499,220,000 2,499,239,000 2,503,543,000 2,137,332,000 2,168,919,000 2,170,169,000 2,115,644,000 2,107,861,000 2,087,406,000 2,037,467,000 2,049,353,000 1,061,779,000 1,067,274,000 1,082,244,000 1,080,500,000 1,073,195,000 1,092,017,000 1,098,426,000 1,119,845,000 1,127,285,000 1,145,218,000 1,145,319,000 974,185,000 983,079,000 969,597,000 973,346,000 965,149,000 976,124,000 969,095,000 974,392,000 977,222,000 1,014,111,000 978,260,000 981,182,000 977,765,000 995,758,000 1,021,066,000 1,000,360,000 1,019,011,000 1,027,579,000 1,170,854,000 1,161,111,000 1,180,329,000 1,199,651,000 1,171,950,000 1,179,990,000 1,207,250,000 336,701,000 301,666,000 292,326,000 289,988,000 303,396,000 250,432,000 199,484,000 194,667,000 193,528,000 190,926,000 185,558,000 118,706,000 117,116,000 125,029,000       
        total assets
      7,552,566,000 7,624,056,000 7,540,299,000 7,439,929,000 7,246,387,000 7,377,278,000 7,306,010,000 7,136,948,000 6,939,823,000 6,382,869,000 6,248,179,000 6,101,337,000 6,129,707,000 6,072,627,000 5,924,656,000 5,726,257,000 5,653,699,000 4,354,299,000 4,275,879,000 4,152,539,000 4,131,520,000 4,106,187,000 4,077,629,000 4,132,021,000 4,108,904,000 4,021,862,000 3,955,321,000 3,882,054,000 3,738,321,000 3,774,329,000 3,715,461,000 3,684,816,000 3,706,570,000 3,748,353,000 3,806,282,000 3,645,653,000 3,681,920,000 3,712,613,000 3,692,381,000 3,641,675,000 3,431,428,000 3,599,861,000 3,746,637,000 3,546,042,000 3,704,278,000 3,761,217,000 3,932,443,000 3,863,955,000 3,953,678,000 3,956,852,000 3,832,113,000 3,803,378,000 3,825,806,000 2,449,403,000 2,122,214,000 2,092,895,000 2,085,803,000 2,010,385,000 1,965,080,000 1,880,644,000 1,566,368,000 1,544,228,000 1,417,191,000 1,364,939,000 898,580,000 873,046,000 920,942,000 955,188,000 760,842,000 732,728,000 700,947,000 650,616,000 677,166,000 
        liabilities and stockholders’ equity
                                                                               
        current liabilities:
                                                                               
        current portion of long-term debt
      12,600,000 12,600,000 15,102,000 15,102,000 15,102,000 15,102,000 15,102,000 15,102,000 15,102,000 10,000,000 10,000,000 10,000,000 10,000,000 17,535,000 17,535,000 17,535,000 17,535,000 7,535,000 7,535,000 7,535,000 7,535,000                                            52,889,000  18,486,000 69,224,000   19,184,000  5,982,000 
        accounts payable
      464,173,000 506,592,000 444,119,000 432,771,000 443,654,000 487,286,000 504,206,000 447,940,000 452,848,000 451,806,000 414,963,000 374,438,000 446,629,000 416,913,000 409,218,000 394,152,000 359,866,000 286,565,000 249,206,000 213,355,000 195,878,000 213,776,000 188,340,000 267,892,000 298,375,000 277,545,000 253,177,000 242,260,000 276,461,000 248,405,000 247,821,000 237,953,000 224,231,000 223,599,000 224,218,000 218,676,000 229,534,000 226,776,000 222,302,000 188,834,000 241,183,000 295,476,000 365,088,000 244,216,000 267,329,000 251,832,000 262,553,000 284,768,000 316,462,000 321,097,000 273,058,000 263,564,000 256,468,000 174,327,000 172,657,000 172,551,000 178,084,000 201,561,000 156,106,000 135,998,000 145,120,000 145,672,000 92,242,000 83,931,000 54,939,000 48,866,000 73,294,000 72,273,000 74,509,000 83,434,000 76,742,000 69,722,000 95,456,000 
        deferred revenue
      82,858,000 81,529,000 91,966,000 87,792,000 96,171,000 88,545,000 103,291,000 108,035,000 106,425,000 95,230,000 102,468,000 105,327,000 94,094,000 93,425,000 94,531,000 90,116,000 83,749,000 86,589,000 83,733,000 83,165,000 74,066,000 67,412,000 61,902,000 71,243,000 73,370,000 73,157,000 75,170,000 67,557,000 61,843,000 65,172,000 68,705,000 68,748,000 67,822,000 69,236,000 72,089,000 64,379,000 64,397,000 66,023,000 70,263,000 63,587,000 61,882,000 62,837,000 64,642,000 62,677,000 62,966,000 63,909,000 61,593,000 56,469,000 55,454,000 61,912,000 63,374,000 62,162,000 50,942,000 29,060,000 32,015,000 29,157,000 32,297,000 28,627,000 28,462,000 28,500,000 28,654,000 28,090,000 22,547,000 21,936,000 23,566,000 21,399,000 25,784,000 23,492,000 25,061,000 30,092,000 30,627,000 28,779,000 29,415,000 
        accrued expenses and other current liabilities
      384,130,000 441,788,000 415,170,000 376,585,000 325,759,000 419,445,000 398,236,000 392,708,000 349,435,000 397,157,000 369,097,000 348,857,000 396,716,000 405,257,000 387,047,000 338,835,000 391,414,000 299,427,000                                                        
        current portion of closure, post-closure and remedial liabilities
      21,129,000 19,112,000 28,814,000 26,524,000 23,792,000 20,625,000 30,477,000 31,954,000 29,179,000 26,914,000 21,759,000 21,802,000 23,123,000 36,904,000 34,551,000 26,393,000 25,136,000 23,288,000 23,865,000 26,896,000 26,093,000 22,324,000 19,129,000 16,231,000 23,301,000 26,986,000 30,747,000 27,914,000 23,034,000 25,256,000 23,007,000 19,823,000 19,782,000 19,516,000 23,700,000 21,569,000 20,016,000 20,217,000 24,043,000 21,497,000 20,395,000 21,902,000 26,321,000 25,124,000 22,091,000 32,742,000 36,043,000 31,866,000 29,471,000 27,737,000 22,470,000 21,575,000 24,121,000 19,552,000 19,801,000 18,653,000 15,059,000 15,899,000 15,626,000 14,761,000 19,925,000 21,308,000 18,615,000 21,872,000 22,400,000 17,838,000 17,073,000 22,795,000 22,061,000 15,803,000 15,448,000 12,418,000 15,965,000 
        current portion of operating lease liabilities
      78,069,000 75,226,000 72,241,000 72,976,000 71,865,000 71,663,000 70,539,000 65,901,000 64,534,000 56,430,000 57,100,000 53,991,000 49,532,000 47,879,000 47,176,000 47,108,000 47,614,000 36,497,000 35,074,000 35,390,000 36,750,000 36,814,000 38,620,000 39,998,000 40,979,000 41,364,000 42,564,000 43,858,000                                              
        total current liabilities
      1,042,959,000 1,136,847,000 1,067,412,000 1,011,750,000 976,343,000 1,102,666,000 1,121,851,000 1,061,640,000 1,017,523,000 1,037,537,000 975,387,000 914,415,000 1,020,094,000 1,017,913,000 990,058,000 914,139,000 925,314,000 739,901,000 711,069,000 650,553,000 636,145,000 641,061,000 604,940,000 658,412,000 720,100,000 680,042,000 633,690,000 597,510,000 602,278,000 576,300,000 543,668,000 524,684,000 503,817,000 529,540,000 619,300,000 488,581,000 504,668,000 539,096,000 520,421,000 465,510,000 517,120,000 625,016,000 697,194,000 519,861,000 572,471,000 608,870,000 606,266,000 587,318,000 639,545,000 669,532,000 604,187,000 564,045,000 569,052,000 365,563,000 361,321,000 342,227,000 381,742,000 393,568,000 325,430,000 282,320,000 314,202,000 320,850,000 218,067,000 232,377,000 214,900,000 150,873,000 211,236,000 261,675,000 192,960,000 202,446,000 214,903,000 166,580,000 212,555,000 
        other liabilities:
                                                                               
        closure and post-closure liabilities, less current portion of 12,132 and 10,290, respectively
      123,334,000                                                                         
        remedial liabilities, less current portion of 8,997 and 8,822, respectively
      85,009,000                                                                         
        long-term debt, less current portion
      2,761,417,000 2,763,563,000 2,764,231,000 2,766,530,000 2,768,815,000 2,771,117,000 2,773,659,000 2,775,837,000 2,778,624,000 2,291,717,000 2,292,952,000 2,294,306,000 2,414,828,000 2,507,946,000 2,510,963,000 2,513,944,000 2,517,024,000 1,546,284,000 1,547,398,000 1,548,517,000 1,549,641,000                                                     
        operating lease liabilities, less current portion
      189,797,000 184,308,000 173,137,000 178,343,000 179,454,000 182,883,000 179,040,000 152,328,000 145,544,000 131,743,000 133,163,000 129,058,000 119,259,000 116,607,000 112,854,000 113,059,000 117,991,000 102,093,000 101,377,000 107,554,000 114,258,000 110,097,000 115,089,000 120,649,000 121,020,000 122,668,000 130,704,000 128,689,000                                              
        deferred tax liabilities
      384,297,000 384,207,000 358,597,000 359,661,000 360,404,000 363,623,000 356,150,000 360,861,000 361,223,000 353,107,000 347,628,000 346,328,000 350,389,000 326,842,000 322,108,000 312,668,000 314,853,000 231,663,000 228,718,000 230,236,000 230,097,000                                                     
        other long-term liabilities
      190,250,000 197,886,000 193,237,000 199,903,000 179,895,000 162,552,000 147,241,000 145,804,000 125,393,000 118,330,000 103,419,000 96,262,000 90,847,000 78,602,000 79,621,000 80,175,000 78,790,000 90,242,000 95,647,000 88,772,000 83,182,000                                                  61,694,000 57,673,000 15,944,000 
        total other liabilities
      3,734,104,000 3,741,549,000 3,697,047,000 3,714,112,000 3,698,820,000 3,701,083,000 3,655,849,000 3,633,587,000 3,610,963,000 3,097,826,000 3,086,998,000 3,077,036,000 3,187,291,000 3,217,133,000 3,217,648,000 3,218,881,000 3,214,498,000 2,150,838,000 2,155,223,000 2,153,536,000 2,153,824,000 2,160,411,000 2,218,718,000 2,267,804,000 2,118,991,000 2,106,025,000 2,112,164,000 2,112,579,000 1,966,287,000 2,000,705,000 2,010,745,000 2,014,606,000 2,014,551,000 2,090,466,000 2,086,045,000 2,093,442,000 2,093,011,000 2,072,572,000 2,055,617,000 2,059,592,000 1,818,026,000 1,852,124,000 1,876,007,000 1,863,332,000 1,868,936,000 1,831,796,000 1,827,461,000 1,831,002,000 1,838,494,000 1,811,200,000 1,813,206,000 1,815,865,000 1,824,682,000 1,077,085,000 799,993,000 799,390,000 803,074,000 776,611,000 782,282,000 776,454,000 514,413,000 543,214,000 557,017,000 541,171,000 235,489,000 288,672,000 289,698,000 288,603,000 356,375,000 352,099,000 326,869,000 342,379,000 298,104,000 
        commitments and contingent liabilities
                                                                               
        stockholders’ equity:
                                                                               
        common stock
                         546,000  552,000 556,000                                                   
        authorized 80,000,000 shares; issued and outstanding 52,833,291 and 52,870,599 shares, respectively
      528,000                                                                         
        additional paid-in capital
      169,172,000 193,896,000 317,145,000 361,598,000 365,698,000 421,749,000 438,904,000 459,982,000 458,014,000 459,728,000 490,163,000 502,422,000 504,240,000 506,359,000 512,662,000 536,564,000 536,377,000 539,747,000 539,390,000 555,966,000 582,749,000 613,208,000 629,755,000 628,140,000 644,412,000 648,184,000 648,805,000 652,624,000 655,415,000 661,546,000 664,948,000 675,230,000 686,962,000 708,358,000 716,712,000 720,383,000 725,670,000 726,878,000 730,709,000 733,726,000 738,401,000 740,070,000 777,465,000 789,501,000 805,029,000 853,350,000 889,080,000 900,726,000 898,165,000 893,822,000 889,588,000 885,733,000 880,979,000 508,182,000 504,667,000 501,014,000 497,919,000 499,086,000 495,237,000 492,264,000 485,629,000 482,377,000 477,312,000 475,487,000 355,026,000 355,332,000 350,573,000 346,585,000 170,105,000 158,022,000 155,185,000 153,446,000 153,902,000 
        accumulated other comprehensive loss
      -213,249,000 -204,616,000 -211,100,000 -198,529,000 -218,567,000 -213,635,000 -192,036,000 -184,490,000 -179,626,000 -175,339,000 -169,139,000 -165,966,000 -167,181,000 -171,567,000 -162,702,000 -162,163,000 -196,012,000 -200,716,000 -188,889,000 -199,529,000 -211,477,000 -239,444,000 -251,829,000 -269,357,000 -210,051,000 -223,690,000 -214,271,000 -219,347,000 -223,371,000 -185,505,000 -194,095,000 -189,153,000 -172,407,000 -169,468,000 -193,177,000 -208,275,000 -214,326,000 -211,544,000 -210,233,000 -209,055,000 -254,892,000 -229,555,000 -176,014,000 -188,245,000 -110,842,000 -74,117,000 -25,025,000 -61,081,000                          
        retained earnings
      2,819,052,000 2,755,851,000 2,669,261,000 2,550,462,000 2,423,557,000 2,364,877,000 2,280,903,000 2,165,690,000 2,032,410,000 1,962,578,000                                                         59,250,000 44,622,000     865,000 
        total stockholders’ equity
      2,775,503,000  2,775,840,000 2,714,067,000 2,571,224,000  2,528,310,000 2,441,721,000 2,311,337,000  2,185,794,000 2,109,886,000  1,837,581,000 1,716,950,000 1,593,237,000  1,463,560,000 1,409,587,000 1,348,450,000  1,304,715,000 1,253,971,000 1,205,805,000  1,235,795,000 1,209,467,000 1,171,965,000  1,197,324,000 1,161,048,000 1,145,526,000  1,128,347,000 1,100,937,000 1,063,630,000  1,100,945,000 1,116,343,000 1,116,573,000  1,122,721,000 1,173,436,000 1,162,849,000  1,320,551,000 1,498,716,000 1,445,635,000  1,476,120,000 1,414,720,000 1,423,468,000  1,006,755,000 960,900,000 951,278,000  840,206,000 857,368,000 821,870,000 737,753,000 680,164,000 642,107,000 589,046,000 448,191,000 433,501,000 420,008,000 404,910,000 211,507,000 178,183,000 159,175,000 141,657,000 166,507,000 
        total liabilities and stockholders’ equity
      7,552,566,000  7,540,299,000 7,439,929,000 7,246,387,000  7,306,010,000 7,136,948,000 6,939,823,000  6,248,179,000 6,101,337,000  6,072,627,000 5,924,656,000 5,726,257,000  4,354,299,000 4,275,879,000 4,152,539,000  4,106,187,000 4,077,629,000 4,132,021,000  4,021,862,000 3,955,321,000 3,882,054,000  3,774,329,000 3,715,461,000 3,684,816,000  3,748,353,000 3,806,282,000 3,645,653,000  3,712,613,000 3,692,381,000 3,641,675,000  3,599,861,000 3,746,637,000 3,546,042,000  3,761,217,000 3,932,443,000 3,863,955,000  3,956,852,000 3,832,113,000 3,803,378,000  2,449,403,000 2,122,214,000 2,092,895,000  2,010,385,000 1,965,080,000 1,880,644,000 1,566,368,000 1,544,228,000 1,417,191,000  898,580,000 873,046,000 920,942,000 955,188,000 760,842,000 732,728,000 700,947,000 650,616,000 677,166,000 
        liabilities and stockholders' equity
                                                                               
        closure and post-closure liabilities, less current portion of 10,290 and 10,304, respectively
       125,038,000                                                                        
        remedial liabilities, less current portion of 8,822 and 10,321, respectively
       86,547,000                                                                        
        stockholders' equity:
                                                                               
        authorized 80,000,000 shares; issued and outstanding 52,870,599 and 53,832,692 shares, respectively
       529,000                                                                        
        total stockholders' equity
       2,745,660,000    2,573,529,000    2,247,506,000   1,922,322,000    1,513,887,000    1,341,551,000    1,269,813,000    1,169,756,000    1,188,202,000    1,084,241,000    1,096,282,000    1,262,871,000    1,475,639,000    1,432,072,000    900,987,000                 
        total liabilities and stockholders' equity
       7,624,056,000    7,377,278,000    6,382,869,000   6,129,707,000    5,653,699,000    4,131,520,000    4,108,904,000    3,738,321,000    3,706,570,000    3,681,920,000    3,431,428,000    3,704,278,000    3,953,678,000    3,825,806,000    2,085,803,000                 
        closure and post-closure liabilities, less current portion of 16,796 and 10,304, respectively
        122,546,000                                                                       
        remedial liabilities, less current portion of 12,018 and 10,321, respectively
        85,299,000                                                                       
        authorized 80,000,000 shares; issued and outstanding 53,430,975 and 53,832,692 shares, respectively
        534,000                                                                       
        closure and post-closure liabilities, less current portion of 14,092 and 10,304, respectively
         122,795,000                                                                      
        remedial liabilities, less current portion of 12,432 and 10,321, respectively
         86,880,000                                                                      
        authorized 80,000,000 shares; issued and outstanding 53,614,135 and 53,832,692 shares, respectively
         536,000                                                                      
        closure and post-closure liabilities, less current portion of 12,948 and 10,304, respectively
          121,221,000                                                                     
        remedial liabilities, less current portion of 10,844 and 10,321, respectively
          89,031,000                                                                     
        authorized 80,000,000 shares; issued and outstanding 53,636,038 and 53,832,692 shares, respectively
          536,000                                                                     
        closure and post-closure liabilities, less current portion of 10,304 and 13,556, respectively
           119,484,000                                                                    
        remedial liabilities, less current portion of 10,321 and 13,358, respectively
           101,424,000                                                                    
        authorized 80,000,000 shares; issued and outstanding 53,832,692 and 53,929,703 shares, respectively
           538,000                                                                    
        closure and post-closure liabilities, less current portion of 14,203 and 13,556, respectively
            105,375,000                                                                   
        remedial liabilities, less current portion of 16,274 and 13,358, respectively
            94,384,000                                                                   
        authorized 80,000,000 shares; issued and outstanding 53,898,805 and 53,929,703 shares, respectively
            539,000                                                                   
        closure and post-closure liabilities, less current portion of 15,813 and 13,556, respectively
             103,299,000                                                                  
        remedial liabilities, less current portion of 16,141 and 13,358, respectively
             95,458,000                                                                  
        authorized 80,000,000 shares; issued and outstanding 53,930,201 and 53,929,703 shares, respectively
             539,000                                                                  
        closure and post-closure liabilities, less current portion of 14,079 and 13,556, respectively
              105,493,000                                                                 
        remedial liabilities, less current portion of 15,100 and 13,358, respectively
              94,686,000                                                                 
        authorized 80,000,000 shares; issued and outstanding 53,926,191 and 53,929,703 shares, respectively
              539,000                                                                 
        closure and post-closure liabilities, less current portion of 13,556 and 13,205, respectively
               105,044,000                                                                
        remedial liabilities, less current portion of 13,358 and 9,918, respectively
               97,885,000                                                                
        authorized 80,000,000 shares; issued and outstanding 53,929,703 and 54,064,797 shares, respectively
               539,000                                                                
        other
                80,211,000 74,315,000 81,803,000 78,032,000 48,449,000 25,812,000 15,602,000 14,825,000 13,042,000 16,580,000 16,516,000 10,079,000 14,893,000 11,392,000 13,560,000 12,539,000 12,817,000 17,901,000 18,121,000 17,622,000 16,426,000 16,006,000 17,498,000 19,757,000 13,448,000 13,580,000 13,347,000 34,944,000 23,133,000 16,381,000 15,995,000 13,724,000 17,646,000 18,142,000 18,682,000 17,725,000 18,938,000 18,802,000 18,536,000 15,806,000 14,491,000 13,081,000 14,651,000 10,311,000 10,604,000 10,519,000 10,100,000 9,166,000 14,481,000 5,728,000 8,222,000 8,304,000 3,980,000 4,060,000 2,553,000 2,623,000 4,194,000 3,842,000 4,052,000 4,652,000 4,591,000 3,781,000 3,403,000 
        closure and post-closure liabilities, less current portion of 11,425 and 13,205, respectively
                108,466,000                                                               
        remedial liabilities, less current portion of 10,334 and 9,918, respectively
                101,370,000                                                               
        authorized 80,000,000 shares; issued and outstanding 54,102,982 and 54,064,797 shares, respectively
                541,000                                                               
        accumulated earnings
                1,864,229,000 1,772,889,000 1,584,722,000 1,502,248,000 1,366,449,000 1,218,292,000 1,172,978,000 1,123,985,000 1,058,542,000 991,467,000 969,731,000 930,399,000 875,489,000 846,466,000 834,894,000 810,743,000 774,374,000 738,130,000 737,154,000 720,723,000 689,634,000 658,887,000 673,082,000 588,888,000 576,830,000 550,950,000 572,793,000 585,506,000 595,761,000 591,795,000 612,666,000 612,098,000 571,870,000 561,475,000 568,564,000 541,187,000 634,524,000 605,852,000 596,892,000 570,091,000 534,730,000 511,828,000 501,326,000 439,452,000 427,093,000 403,667,000 371,652,000 333,419,000 296,286,000 267,130,000 221,071,000 182,244,000 124,315,000 99,963,000 90,778,000 82,154,000   28,635,000 3,144,000    
        closure and post-closure liabilities, less current portion of 12,186 and 13,205, respectively
                 108,522,000                                                              
        remedial liabilities, less current portion of 9,616 and 9,918, respectively
                 102,560,000                                                              
        authorized 80,000,000 shares; issued and outstanding 54,090,202 and 54,064,797 shares, respectively
                 541,000                                                              
        closure and post-closure liabilities, less current portion of 13,205 and 12,015, respectively
                  105,596,000                                                             
        remedial liabilities, less current portion of 9,918 and 13,121, respectively
                  106,372,000                                                             
        authorized 80,000,000 shares; issued and outstanding 54,064,797 and 54,419,321 shares, respectively
                  541,000                                                             
        closure and post-closure liabilities, less current portion of 17,373 and 12,015, respectively
                   89,399,000                                                            
        remedial liabilities, less current portion of 19,531 and 13,121, respectively
                   97,737,000                                                            
        authorized 80,000,000 shares; issued and outstanding 54,070,197 and 54,419,321 shares, respectively
                   541,000                                                            
        closure and post-closure liabilities, less current portion of 12,379 and 12,015, respectively
                    90,618,000                                                           
        remedial liabilities, less current portion of 22,172 and 13,121, respectively
                    101,484,000                                                           
        authorized 80,000,000 shares; issued and outstanding 54,110,459 and 54,419,321 shares, respectively
                    541,000                                                           
        closure and post-closure liabilities, less current portion of 7,808 and 12,015, respectively
                     92,891,000                                                          
        remedial liabilities, less current portion of 18,585 and 13,121, respectively
                     106,144,000                                                          
        authorized 80,000,000 shares; issued and outstanding 54,414,189 and 54,419,321 shares, respectively
                     544,000                                                          
        closure and post-closure liabilities, less current portion of 12,015 and 13,903, respectively
                      87,088,000                                                         
        remedial liabilities, less current portion of 13,121 and 12,190, respectively
                      98,752,000                                                         
        authorized 80,000,000 shares; issued and outstanding 54,419,321 and 54,772,696 shares, respectively
                      544,000                                                         
        closure and post-closure liabilities, less current portion of 10,219 and 13,903, respectively
                       82,809,000                                                        
        remedial liabilities, less current portion of 13,069 and 12,190, respectively
                       97,747,000                                                        
        authorized 80,000,000 shares; issued and outstanding 54,409,894 and 54,772,696 shares, respectively
                       544,000                                                        
        accrued expenses
                        311,656,000 284,212,000 295,823,000 293,200,000 289,414,000 255,513,000 276,540,000 253,455,000 224,497,000 208,386,000 233,405,000 229,932,000 200,135,000 194,160,000 187,982,000 213,189,000 191,495,000 183,957,000 190,721,000 226,080,000 203,813,000 191,592,000 193,660,000 244,790,000 241,098,000 187,728,000 219,549,000 260,123,000 245,368,000 213,096,000 236,829,000 256,813,000 242,362,000 212,424,000 232,429,000 136,687,000 130,526,000 114,501,000 147,992,000 138,911,000 118,716,000 95,847,000 115,377,000 120,644,000 79,178,000 89,144,000 55,911,000 55,473,000        
        closure and post-closure liabilities, less current portion of 9,752 and 13,903, respectively
                        83,742,000                                                       
        remedial liabilities, less current portion of 14,113 and 12,190, respectively
                        98,341,000                                                       
        authorized 80,000,000 shares; issued and outstanding 54,393,252 and 54,772,696 shares, respectively
                        544,000                                                       
        closure and post-closure liabilities, less current portion of 11,887 and 13,903, respectively
                         79,218,000                                                      
        remedial liabilities, less current portion of 15,009 and 12,190, respectively
                         99,239,000                                                      
        closure and post-closure liabilities, less current portion of 13,903 and 7,283, respectively
                          74,023,000                                                     
        remedial liabilities, less current portion of 12,190 and 16,018, respectively
                          102,623,000                                                     
        authorized 80,000,000 shares; issued and outstanding 54,772,696 and 55,797,734 shares, respectively
                          548,000                                                     
        deferred costs
                           20,212,000 18,715,000 21,270,000 21,746,000 21,939,000 22,500,000 20,515,000 18,770,000 19,849,000 20,832,000 20,847,000 20,445,000 20,237,000 21,054,000 19,037,000 18,914,000 19,970,000 21,261,000 19,346,000 18,758,000 19,096,000 19,575,000 18,880,000 19,018,000 18,676,000 17,909,000 16,523,000 16,134,000 17,097,000 17,255,000 16,987,000 6,888,000 6,995,000 7,273,000 5,787,000 5,903,000 5,831,000 6,289,000 6,359,000 7,067,000 6,844,000 5,312,000 5,264,000 5,691,000 5,116,000 6,382,000 5,795,000 6,136,000 7,499,000 7,622,000 6,899,000 6,248,000 
        current portion of long-term obligations
                           7,535,000 7,535,000 7,535,000 7,535,000 7,535,000 7,535,000 7,535,000 7,535,000 7,535,000 4,000,000 4,000,000 4,000,000 4,000,000 107,798,000                                       
        closure and post-closure liabilities, less current portion of 7,146 and 7,283, respectively
                           77,070,000                                                    
        remedial liabilities, less current portion of 15,178 and 16,018, respectively
                           100,389,000                                                    
        long-term obligations, less current portion
                           1,550,756,000 1,626,871,000 1,702,992,000 1,554,116,000 1,555,257,000 1,562,989,000 1,564,005,000 1,565,021,000 1,616,156,000 1,624,727,000 1,625,259,000 1,625,537,000 1,625,971,000 1,626,505,000                                       
        deferred taxes, unrecognized tax benefits and other long-term liabilities
                           322,099,000 300,763,000 269,091,000 277,332,000 263,658,000 255,113,000 254,417,000 233,352,000 221,712,000 222,246,000 222,643,000 223,291,000 298,659,000 297,288,000 294,085,000 293,417,000 268,564,000 258,302,000 260,017,000 267,637,000 282,447,000 306,705,000 292,591,000 290,205,000 255,804,000 249,968,000 244,795,000 246,947,000 217,683,000 215,187,000 215,365,000 224,456,000                     
        closure and post-closure liabilities, less current portion of 5,708 and 7,283, respectively
                            76,933,000                                                   
        remedial liabilities, less current portion of 13,421 and 16,018, respectively
                            99,062,000                                                   
        closure and post-closure liabilities, less current portion of 4,333 and 7,283, respectively
                             76,106,000                                                  
        remedial liabilities, less current portion of 11,898 and 16,018, respectively
                             98,966,000                                                  
        authorized 80,000,000 shares; issued and outstanding 55,554,925 and 55,797,734 shares, respectively
                             556,000                                                  
        closure and post-closure liabilities, less current portion of 7,283 and 9,592, respectively
                              68,368,000                                                 
        remedial liabilities, less current portion of 16,018 and 13,442, respectively
                              98,155,000                                                 
        authorized 80,000,000 shares; issued and outstanding 55,797,734 and 55,847,261 shares, respectively
                              558,000                                                 
        closure and post-closure liabilities, less current portion of 9,896 and 9,592, respectively
                               64,263,000                                                
        remedial liabilities, less current portion of 17,090 and 13,442, respectively
                               100,179,000                                                
        authorized 80,000,000 shares; issued and outstanding 55,807,524 and 55,847,261 shares, respectively
                               558,000                                                
        closure and post-closure liabilities, less current portion of 13,491 and 9,592, respectively
                                62,339,000                                               
        remedial liabilities, less current portion of 17,256 and 13,442, respectively
                                101,019,000                                               
        authorized 80,000,000; shares issued and outstanding 55,859,402 and 55,847,261 shares, respectively
                                559,000                                               
        closure and post-closure liabilities, less current portion of 12,337 and 9,592, respectively
                                 62,084,000                                              
        remedial liabilities, less current portion of 15,577 and 13,442, respectively
                                 103,384,000                                              
        authorized 80,000,000; shares issued and outstanding 55,827,714 and 55,847,261 shares, respectively
                                 558,000                                              
        closure and post-closure liabilities, less current portion of 9,592 and 6,444, respectively
                                  60,339,000                                             
        remedial liabilities, less current portion of 13,442 and 13,338, respectively
                                  107,575,000                                             
        authorized 80,000,000 shares; issued and outstanding 55,847,261 and 56,501,190 shares, respectively
                                  558,000                                             
        closure and post-closure liabilities, less current portion of 9,576 and 6,444, respectively
                                   57,805,000                                            
        remedial liabilities, less current portion of 15,680 and 13,338, respectively
                                   105,032,000                                            
        authorized 80,000,000; shares issued and outstanding 55,997,893 and 56,501,190 shares, respectively
                                   560,000                                            
        closure and post-closure liabilities, less current portion of 6,514 and 6,444, respectively
                                    58,990,000                                           
        remedial liabilities, less current portion of 16,493 and 13,338, respectively
                                    104,782,000                                           
        authorized 80,000,000; shares issued and outstanding 56,087,256 and 56,501,190 shares, respectively
                                    561,000                                           
        closure and post-closure liabilities, less current portion of 5,519 and 6,444, respectively
                                     58,561,000                                          
        remedial liabilities, less current portion of 14,304 and 13,338, respectively
                                     108,143,000                                          
        authorized 80,000,000; shares issued and outstanding 56,244,601 and 56,501,190 shares, respectively
                                     562,000                                          
        closure and post-closure liabilities, less current portion of 6,444 and 6,220, respectively
                                      54,593,000                                         
        remedial liabilities, less current portion of 13,338 and 13,796, respectively
                                      111,130,000                                         
        authorized 80,000,000 shares; issued and outstanding 56,501,190 and 57,297,978 shares, respectively
                                      565,000                                         
        shares held under employee participation plan
                                          -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -469,000 -777,000                
        closure and post-closure liabilities, less current portion of 4,077 and 6,220, respectively
                                       55,762,000                                        
        remedial liabilities, less current portion of 15,439 and 13,796, respectively
                                       110,074,000                                        
        authorized 80,000,000; shares issued and outstanding 56,926,549 and 57,297,978 shares, respectively
                                       569,000                                        
        closure and post-closure liabilities, less current portion of 6,745 and 6,220, respectively
                                        53,048,000                                       
        remedial liabilities, less current portion of 16,955 and 13,796, respectively
                                        109,204,000                                       
        authorized 80,000,000; shares issued and outstanding 57,153,687 and 57,297,978 shares, respectively
                                        572,000                                       
        closure and post-closure liabilities, less current portion of 6,019 and 6,220, respectively
                                         54,332,000                                      
        remedial liabilities, less current portion of 15,550 and 13,796, respectively
                                         111,057,000                                      
        long-term obligations
                                         1,633,968,000 1,633,272,000 1,632,577,000 1,631,881,000 1,631,603,000 1,382,543,000 1,395,000,000 1,395,000,000 1,395,000,000 1,395,000,000 1,395,000,000 1,395,000,000 1,400,000,000 1,400,000,000 1,400,000,000 1,400,000,000 1,400,000,000 1,400,000,000 800,000,000 523,481,000 523,833,000 524,203,000 524,590,000 524,994,000 525,416,000 263,799,000 292,874,000 292,651,000 292,219,000  52,880,000   120,746,000     
        authorized 80,000,000; shares issued and outstanding 57,188,805 and 57,297,978 shares, respectively
                                         572,000                                      
        closure and post-closure liabilities, less current portion of 6,220 and 7,229, respectively
                                          52,111,000                                     
        remedial liabilities, less current portion of 13,796 and 13,166, respectively
                                          114,211,000                                     
        authorized 80,000,000 shares; issued and outstanding 57,297,978 and 57,593,201 shares, respectively
                                          573,000                                     
        deferred financing costs
                                           1,197,000 1,412,000 1,627,000 1,847,000 15,121,000 15,941,000 16,761,000 17,580,000 18,403,000 19,284,000 20,036,000 20,860,000 21,565,000 22,410,000 23,239,000 21,657,000 12,530,000 12,152,000 12,872,000 13,607,000 14,325,000 15,061,000 12,941,000 7,958,000 9,175,000 9,694,000 10,356,000 2,308,000 2,688,000 3,776,000 5,228,000 5,306,000 6,325,000 6,754,000 7,182,000 7,602,000 
        closure and post-closure liabilities, less current portion of 6,057 and 7,229, respectively
                                           56,510,000                                    
        remedial liabilities, less current portion of 14,160 and 13,166, respectively
                                           114,921,000                                    
        authorized 80,000,000; shares issued and outstanding 57,389,531 and 57,593,201 shares, respectively
                                           574,000                                    
        closure and post-closure liabilities, less current portion of 8,043 and 7,229, respectively
                                            51,143,000                                   
        remedial liabilities, less current portion of 16,000 and 13,166, respectively
                                            114,291,000                                   
        authorized 80,000,000; shares issued and outstanding 57,495,095 and 57,593,201 shares, respectively
                                            575,000                                   
        closure and post-closure liabilities, less current portion of 7,194 and 7,229, respectively
                                             50,896,000                                  
        remedial liabilities, less current portion of 14,303 and 13,166, respectively
                                             117,076,000                                  
        authorized 80,000,000; shares issued and outstanding 57,551,188 and 57,593,201 shares, respectively
                                             576,000                                  
        deferred tax assets
                                               37,288,000 37,410,000 36,355,000 36,532,000 32,141,000 32,239,000 32,469,000 32,517,000 21,898,000 20,924,000 25,371,000 22,577,000 16,617,000 16,605,000 16,426,000 16,602,000 16,488,000 18,884,000 17,364,000 19,878,000 18,748,000 19,114,000 12,415,000 12,324,000 12,514,000 11,497,000 11,497,000 11,497,000 9,343,000 9,299,000 9,281,000 5,777,000 
        current portion of capital lease obligations
                                               11,000 45,000 116,000 536,000 264,000 709,000 1,119,000 1,329,000 1,973,000 2,923,000 4,320,000 5,092,000 5,937,000 6,322,000 7,365,000 8,310,000 8,570,000 6,520,000 7,214,000 5,126,000 5,136,000 1,963,000 1,870,000 176,000 189,000 484,000 482,000 478,000 1,014,000 1,048,000 1,193,000 1,602,000 
        closure and post-closure liabilities, less current portion of 7,229 and 4,999, respectively
                                              49,020,000                                 
        remedial liabilities, less current portion of 13,166 and 17,092, respectively
                                              118,826,000                                 
        authorized 80,000,000 shares; issued and outstanding 57,593,201 and 58,903,482 shares, respectively
                                              576,000                                 
        closure and post-closure liabilities, less current portion of 5,403 and 4,999, respectively
                                               47,861,000                                
        remedial liabilities, less current portion of 16,499 and 17,092, respectively
                                               126,816,000                                
        authorized 80,000,000; shares issued and outstanding 57,664,992 and 58,903,482 shares, respectively
                                               577,000                                
        closure and post-closure liabilities, less current portion of 7,693 and 4,999, respectively
                                                44,153,000                               
        remedial liabilities, less current portion of 18,628 and 17,092, respectively
                                                130,149,000                               
        authorized 80,000,000; shares issued and outstanding 58,428,068 and 58,903,482 shares, respectively
                                                584,000                               
        closure and post-closure liabilities, less current portion of 8,272 and 4,999, respectively
                                                 42,848,000                              
        remedial liabilities, less current portion of 16,852 and 17,092, respectively
                                                 132,893,000                              
        authorized 80,000,000; shares issued and outstanding 58,661,384 and 58,903,482 shares, respectively
                                                 587,000                              
        marketable securities
                                                     213,000 12,435,000 11,787,000 10,339,000 10,905,000 11,778,000 11,113,000 9,701,000 4,997,000 111,000 93,000 128,000 4,143,000 2,821,000 1,331,000 4,412,000 804,000 484,000 270,000 428,000 438,000 1,500,000 11,250,000 11,275,000 11,117,000 10,299,000 
        closure and post-closure liabilities, less current portion of 4,999 and 5,884, respectively
                                                  45,702,000                             
        remedial liabilities, less current portion of 17,092 and 23,587, respectively
                                                  138,029,000                             
        capital lease obligations, less current portion
                                                   733,000 827,000 913,000 1,435,000 1,669,000 2,140,000 2,154,000 2,879,000 3,477,000 4,482,000 5,406,000 6,375,000 7,531,000 9,109,000 6,216,000 10,972,000 11,274,000 6,659,000 7,265,000 259,000 295,000 421,000 556,000 616,000 2,045,000 2,619,000 2,657,000 2,924,000 
        authorized 80,000,000 shares; issued and outstanding 58,903,482 and 60,672,180 shares, respectively
                                                  589,000                             
        closure and post-closure liabilities, less current portion of 3,839 and 5,884, respectively
                                                   46,287,000                            
        remedial liabilities, less current portion of 28,903 and 23,587, respectively
                                                   133,972,000                            
        authorized 80,000,000; shares issued and outstanding 59,947,866 and 60,672,180 shares, respectively
                                                   600,000                            
        closure and post-closure liabilities, less current portion of 6,252 and 5,884, respectively
                                                    43,630,000                           
        remedial liabilities, less current portion of 29,791 and 23,587, respectively
                                                    138,036,000                           
        authorized 80,000,000; shares issued and outstanding 60,579,425 and 60,672,180 shares, respectively
                                                    606,000                           
        closure and post-closure liabilities, less current portion of 7,629 and 5,884, respectively
                                                     40,809,000                          
        remedial liabilities, less current portion of 24,237 and 23,587, respectively
                                                     144,485,000                          
        authorized 80,000,000; shares issued and outstanding 60,717,774 and 60,672,180 shares, respectively
                                                     607,000                          
        closure and post-closure liabilities, less current portion of 5,884 and 8,791, respectively
                                                      41,201,000                         
        remedial liabilities, less current portion of 23,587 and 19,545, respectively
                                                      148,911,000                         
        authorized 80,000,000 shares; issued and outstanding 60,672,180 and 60,385,453 shares, respectively
                                                      607,000                         
        accumulated other comprehensive income
                                                      -19,556,000 12,070,000 -9,735,000 25,771,000 49,632,000 59,056,000 29,076,000 46,533,000 31,353,000 12,222,000 70,366,000 67,240,000 34,206,000 18,611,000 43,451,000 16,881,000 4,042,000  11,609,000 15,026,000 14,014,000 17,388,000 14,136,000 9,515,000 11,542,000 
        long-term investments
                                                       4,352,000 4,352,000 4,354,000 4,354,000 4,326,000 4,326,000 4,245,000 4,245,000 4,239,000 5,311,000 5,379,000 5,430,000 5,315,000 6,503,000 6,503,000 6,483,000 6,312,000 6,625,000 6,625,000 6,116,000     
        closure and post-closure liabilities, less current portion of 7,512 and 8,791, respectively
                                                       39,982,000                        
        remedial liabilities, less current portion of 20,225 and 15,330, respectively
                                                       151,866,000                        
        authorized 80,000,000; shares issued and outstanding 60,612,702 and 60,385,453 shares, respectively
                                                       606,000                        
        closure and post-closure liabilities, less current portion of 5,732 and 8,791, respectively
                                                        40,896,000                       
        remedial liabilities, less current portion of 16,738 and 15,330, respectively
                                                        154,983,000                       
        authorized 80,000,000; shares issued and outstanding 60,550,064 and 60,385,453 shares, respectively
                                                        606,000                       
        closure and post-closure liabilities, less current portion of 3,683 and 8,791, respectively
                                                         41,670,000                      
        remedial liabilities, less current portion of 17,892 and 15,330, respectively
                                                         156,676,000                      
        authorized 80,000,000; shares issued and outstanding 60,491,452 and 60,385,453 shares, respectively
                                                         605,000                      
        closure and post-closure liabilities, less current portion of 8,791 and 3,885, respectively
                                                          45,457,000                     
        remedial liabilities, less current portion of 15,330 and 11,174, respectively
                                                          151,890,000                     
        authorized 80,000,000 shares; issued and outstanding 60,385,453 and 53,182,859 shares, respectively
                                                          604,000                     
        supplies inventories
                                                           63,934,000 57,782,000 57,695,000 56,242,000 53,614,000 47,270,000 43,817,000 42,690,000 40,962,000 41,440,000 39,267,000 27,938,000 27,119,000 27,196,000 24,660,000 23,395,000 22,933,000 21,580,000 20,742,000 19,001,000 
        property, plant and equipment:
                                                                               
        land
                                                           37,735,000 37,171,000 37,377,000 37,185,000 36,664,000 32,782,000 32,751,000 30,871,000 29,255,000 29,415,000 30,187,000 26,832,000 26,726,000 26,570,000 26,632,000 26,217,000 22,276,000 22,129,000 15,860,000 15,665,000 
        asset retirement costs
                                                           2,565,000 2,544,000 2,552,000 2,529,000 2,353,000 2,371,000 2,249,000 2,235,000 2,229,000 2,238,000 1,849,000 1,767,000 1,758,000 1,780,000 1,786,000 1,784,000 1,437,000 1,427,000 1,416,000 1,421,000 
        landfill assets
                                                           69,544,000 61,056,000 57,743,000 58,466,000 51,935,000 52,514,000 51,146,000 51,976,000 48,849,000 49,685,000 45,645,000 42,562,000 38,812,000 35,084,000 34,937,000 33,916,000 24,145,000 21,656,000 18,804,000 12,265,000 
        buildings and improvements
                                                           196,612,000 193,717,000 192,514,000 189,445,000 184,242,000 158,705,000 148,913,000 144,875,000 141,874,000 142,352,000 139,345,000 133,494,000 131,722,000 127,103,000 122,457,000 118,543,000 108,376,000 107,083,000 105,884,000 103,308,000 
        camp equipment
                                                           136,797,000 130,340,000 112,482,000 110,242,000 102,683,000 99,611,000 70,987,000 60,097,000 56,775,000 58,396,000 51,535,000          
        vehicles
                                                           281,690,000 259,315,000 248,361,000 231,980,000 218,111,000 206,388,000 176,983,000 153,037,000 136,761,000 125,343,000 138,829,000 46,539,000 45,387,000 31,571,000 31,629,000 32,497,000 27,391,000 25,748,000 25,469,000 23,738,000 
        equipment
                                                           806,177,000 768,502,000 749,395,000 729,154,000 696,638,000 675,494,000 562,446,000 510,477,000 495,484,000 500,978,000 458,318,000 323,876,000 315,249,000 303,826,000 300,053,000 285,983,000 264,053,000 257,470,000 252,994,000 243,324,000 
        furniture and fixtures
                                                           3,993,000 3,988,000 3,832,000 3,759,000 3,635,000 3,700,000 2,600,000 2,259,000 1,705,000 1,698,000 1,695,000 1,693,000 1,663,000 1,648,000 1,632,000 1,554,000 1,419,000 1,402,000 1,401,000 1,384,000 
        construction in progress
                                                           51,466,000 39,641,000 31,827,000 24,522,000 32,841,000 43,150,000 38,173,000 26,589,000 20,186,000 14,003,000 13,420,000 11,405,000 11,649,000 14,741,000 15,263,000 17,209,000 26,064,000 22,929,000 17,786,000 27,360,000 
        less—accumulated depreciation and amortization
                                                           583,165,000 541,234,000 517,399,000 483,335,000 448,383,000 426,439,000 402,964,000 355,092,000 333,898,000 327,085,000 293,765,000 275,531,000 263,251,000 247,925,000 238,871,000 229,449,000 217,476,000 207,928,000 198,887,000 184,354,000 
        total property, plant and equipment
                                                           1,003,414,000 955,040,000 918,684,000 903,947,000 880,719,000 848,276,000 683,284,000 627,324,000 599,220,000 597,023,000 587,058,000 312,637,000  294,398,000       
        closure and post-closure liabilities, less current portion of 6,921 and 3,885, respectively
                                                           29,712,000                    
        remedial liabilities, less current portion of 12,631 and 11,174, respectively
                                                           117,981,000                    
        unrecognized tax benefits and other long-term liabilities
                                                           125,915,000 124,327,000 119,706,000 117,354,000 92,887,000 91,725,000 86,940,000 83,332,000 82,250,000 93,853,000 81,988,000 76,792,000 74,476,000 73,841,000 71,979,000 70,550,000     
        authorized 80,000,000; shares issued and outstanding 53,386,280 and 53,182,859 shares, respectively
                                                           534,000                    
        permits and other intangibles, net of accumulated amortization of 80,000 and 72,544, respectively
                                                            138,622,000                   
        closure and post-closure liabilities, less current portion of 6,407 and 3,885, respectively
                                                            29,140,000                   
        remedial liabilities, less current portion of 13,394 and 11,174, respectively
                                                            118,563,000                   
        authorized 80,000,000; shares issued and outstanding 53,319,029 and 53,182,859 shares, respectively
                                                            533,000                   
        permits and other intangibles, net of accumulated amortization of 76,989 and 72,544, respectively
                                                             138,967,000                  
        closure and post-closure liabilities, less current portion of 5,538 and 3,885, respectively
                                                             28,560,000                  
        remedial liabilities, less current portion of 13,115 and 11,174, respectively
                                                             121,885,000                  
        authorized 80,000,000; shares issued and outstanding 53,256,146 and 53,182,859 shares, respectively
                                                             533,000                  
        permits and other intangibles, net of accumulated amortization of 72,544 and 60,633, respectively
                                                              139,644,000                 
        closure and post-closure liabilities, less current portion of 3,885 and 5,849, respectively
                                                              30,996,000                 
        remedial liabilities, less current portion of 11,174 and 8,669, respectively
                                                              124,146,000                 
        authorized 80,000,000 shares; issued and outstanding 53,182,859 and 52,772,392 shares, respectively
                                                              532,000                 
        treasury stock
                                                               -4,274,000                
        permits and other intangibles, net of accumulated amortization of 68,531 and 60,633, respectively
                                                               140,970,000                
        closure and post-closure liabilities, less current portion of 5,086 and 5,849, respectively
                                                               27,420,000                
        remedial liabilities, less current portion of 10,813 and 8,669, respectively
                                                               124,183,000                
        authorized 80,000,000; shares issued and outstanding 53,038,399 and 52,772,392 shares, respectively
                                                               530,000                
        permits and other intangibles, net of accumulated amortization of 67,035 and 60,633, respectively
                                                                127,068,000               
        closure and post-closure liabilities, less current portion of 6,313 and 5,849, respectively
                                                                28,595,000               
        remedial liabilities, less current portion of 9,313 and 8,669, respectively
                                                                127,859,000               
        authorized 80,000,000; shares issued and outstanding 52,986,122 and 52,772,392 shares, respectively
                                                                530,000               
        permits and other intangibles, net of accumulated amortization of 63,996 and 60,633, respectively
                                                                 113,650,000              
        closure and post-closure liabilities, less current portion of 5,061 and 5,849, respectively
                                                                 29,877,000              
        remedial liabilities, less current portion of 9,700 and 8,669, respectively
                                                                 128,005,000              
        authorized 40,000,000 shares; issued and outstanding 26,450,206 and 26,386,196 shares, respectively
                                                                 264,000              
        assets held for sale
                                                                    15,135,000 20,232,000          
        permits and other intangibles, net of accumulated amortization of 57,203 and 48,981, respectively
                                                                  114,500,000             
        liabilities held for sale
                                                                    3,522,000 3,218,000          
        closure and post-closure liabilities, less current portion of 8,005 and 7,305, respectively
                                                                  27,952,000             
        remedial liabilities, less current portion of 11,920 and 11,107, respectively
                                                                  128,358,000             
        authorized 40,000,000 shares; issued and outstanding 26,345,685 and 26,230,803 shares, respectively
                                                                  263,000             
        permits and other intangibles, net of accumulated amortization of 54,009 and 48,981, respectively
                                                                   113,737,000            
        closure and post-closure liabilities, less current portion of 9,069 and 7,305, respectively
                                                                   27,923,000            
        remedial liabilities, less current portion of 12,239 and 11,107, respectively
                                                                   128,893,000            
        authorized 40,000,000 shares; issued and outstanding 26,306,089 and 26,230,803 shares, respectively
                                                                   263,000            
        permits and other intangibles, net of accumulated amortization of 52,031 and 48,981, respectively
                                                                    114,036,000           
        closure and post-closure liabilities, less current portion of 7,131 and 7,305, respectively
                                                                    30,224,000           
        remedial liabilities, less current portion of 11,484 and 11,107, respectively
                                                                    133,630,000           
        authorized 40,000,000 shares; issued and outstanding 26,250,495 and 26,230,803 shares, respectively
                                                                    262,000           
        permits and other intangibles, net of accumulated amortization of 46,107 and 40,303, respectively
                                                                     114,940,000          
        uncashed checks
                                                                     10,406,000 5,019,000 7,108,000 6,966,000 7,531,000 6,854,000 4,724,000 14,364,000 6,919,000 4,797,000 
        closure and post-closure liabilities, less current portion of 10,315 and 6,383, respectively
                                                                     23,994,000          
        remedial liabilities, less current portion of 11,557 and 10,881, respectively
                                                                     135,705,000          
        noncontrolling interest
                                                                     2,345,000          
        authorized 40,000,000 shares; issued and outstanding 26,206,384 and 23,733,257 shares, respectively
                                                                     262,000          
        total liabilities, noncontrolling interest and stockholders’ equity
                                                                     1,364,939,000          
        permits and other intangibles, net of accumulated amortization of 43,141 and 40,303, respectively
                                                                      71,056,000         
        closure and post-closure liabilities, less current portion of 8,610 and 6,383, respectively
                                                                      24,982,000         
        remedial liabilities, less current portion of 13,790 and 10,881, respectively
                                                                      133,456,000         
        authorized 40,000,000 shares; issued and outstanding 23,789,835 and 23,733,257 shares, respectively
                                                                      238,000         
        permits and other intangibles, net of accumulated amortization of 41,263 and 40,303, respectively
                                                                       70,264,000        
        closure and post-closure liabilities, less current portion of 5,376 and 6,383, respectively
                                                                       27,432,000        
        remedial liabilities, less current portion of 12,462 and 10,881, respectively
                                                                       133,589,000        
        authorized 40,000,000 shares; issued and outstanding 23,757,541 and 23,733,257 shares, respectively
                                                                       238,000        
        properties held for sale
                                                                         374,000 374,000 908,000 890,000 7,327,000 8,131,000 
        permits and other intangibles, net of accumulated amortization of 39,971 and 36,443, respectively
                                                                        76,228,000       
        other accrued expenses
                                                                        68,977,000 65,878,000 60,346,000 55,333,000 49,143,000 42,569,000 51,008,000 
        income taxes payable
                                                                        172,000  3,651,000 12,046,000 5,431,000 2,092,000 5,070,000 
        closure and post-closure liabilities, less current portion of 6,333 and 5,527, respectively
                                                                        25,746,000       
        remedial liabilities, less current portion of 10,740 and 13,331, respectively
                                                                        136,968,000       
        long-term debt
                                                                        52,722,000 51,557,000      
        authorized 40,000,000 shares; issued and outstanding 23,505,582 and 20,327,533 shares, respectively
                                                                        235,000       
        permits and other intangibles, net of accumulated amortization of 39,035 and 36,443, respectively
                                                                         77,805,000      
        closure and post-closure liabilities, less current portion of 5,896 and 5,527, respectively
                                                                         25,877,000      
        remedial liabilities, less current portion of 16,899 and 13,331, respectively
                                                                         138,634,000      
        authorized 40,000,000 shares; issued and outstanding 23,367,030 and 20,327,533 shares, respectively
                                                                         234,000      
        permits and other intangibles, net of accumulated amortization of 37,465 and 36,443, respectively
                                                                          82,553,000     
        closure and post-closure liabilities, less current portion of 6,227 and 5,527, respectively
                                                                          25,134,000     
        remedial liabilities, less current portion of 15,834 and 13,331, respectively
                                                                          139,329,000     
        authorized 40,000,000 shares; issued and outstanding 20,433,117 and 20,327,533 shares, respectively
                                                                          204,000     
        permits and other intangibles, net of accumulated amortization of 35,126 and 30,386, respectively
                                                                           72,781,000    
        investment in joint venture
                                                                              2,103,000 
        closure and post-closure liabilities, less current portion of 4,655 and 2,035, respectively
                                                                           24,085,000    
        remedial liabilities, less current portion of 11,148 and 11,672, respectively
                                                                           140,189,000    
        long-term obligations, less current maturities
                                                                           120,678,000 101,462,000 120,549,000 120,491,000 
        tax contingencies and other long-term liabilities
                                                                           65,102,000    
        preferred stock, .01 par value:
                                                                               
        series b convertible preferred stock; authorized 156,416 shares; issued and outstanding 68,810 and 69,000 shares, respectively
                                                                           1,000    
        authorized 40,000,000 shares; issued and outstanding 19,881,032 and 19,685,002 shares, respectively
                                                                           199,000    
        income taxes receivable
                                                                            164,000 151,000 673,000 
        permits and other intangibles, net of accumulated amortization of 33,360 and 30,386, respectively
                                                                            67,566,000   
        accrued disposal costs
                                                                            2,916,000 2,888,000 3,260,000 
        closure and post-closure liabilities, less current portion of 4,321 and 2,035, respectively
                                                                            23,302,000   
        remedial liabilities, less current portion of 11,127 and 11,672, respectively
                                                                            137,045,000   
        accrued pension cost
                                                                            747,000 755,000 748,000 
        series b convertible preferred stock; authorized 154,416 shares; issued and outstanding 68,810 and 69,000 shares, respectively
                                                                            1,000 1,000  
        authorized 40,000,000 shares; issued and outstanding 19,848,812 and 19,685,002 shares, respectively
                                                                            198,000   
        accumulated (deficit) earnings
                                                                               
        permits and other intangibles, net of accumulated amortization of 31,655 and 30,386, respectively
                                                                             65,967,000  
        closure and post-closure liabilities, less current portion of 1,900 and 2,035, respectively
                                                                             24,526,000  
        remedial liabilities, less current portion of 10,518 and 11,672, respectively
                                                                             136,219,000  
        authorized 40,000,000 shares; issued and outstanding 19,796,551 and 19,685,002 shares, respectively
                                                                             198,000  
        restricted cash
                                                                               
        permits and other intangibles, net of accumulated amortization of 33,909 and 27,954, respectively
                                                                              66,465,000 
        closure and post-closure liabilities, less current portion of 4,727 and 2,894, respectively
                                                                              20,846,000 
        remedial liabilities, less current portion of 11,238 and 7,923, respectively
                                                                              137,151,000 
        series b convertible preferred stock; authorized 154,416 shares; issued and outstanding 69,000 shares
                                                                              1,000 
        authorized 40,000,000 shares; issued and outstanding 19,650,105 and 19,352,878 shares, respectively
                                                                              197,000 
        restricted stock unearned compensation
                                                                               
      Cashflow Statements:
      Quarterly
      Annual
        Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-12-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2022-12-31 2022-09-30 2022-06-30 2022-03-31 2021-12-31 2021-09-30 2021-06-30 2021-03-31 2020-12-31 2020-09-30 2020-06-30 2020-03-31 2019-12-31 2019-09-30 2019-06-30 2019-03-31 2018-12-31 2018-09-30 2018-06-30 2018-03-31 2017-12-31 2017-09-30 2017-06-30 2017-03-31 2016-12-31 2016-09-30 2016-06-30 2016-03-31 2015-12-31 2015-09-30 2015-06-30 2015-03-31 2014-12-31 2014-09-30 2014-06-30 2014-03-31 2013-12-31 2013-09-30 2013-06-30 2013-03-31 2012-12-31 2012-09-30 2012-06-30 2012-03-31 2011-12-31 2011-09-30 2011-06-30 2011-03-31 2010-09-30 2010-06-30 2010-03-31 2009-09-30 2009-06-30 2009-03-31 2008-09-30 2008-06-30 2008-03-31 2007-09-30 2007-06-30 2007-03-31 
                                                                               
          cash flows from operating activities:
                                                                               
          net income
        63,201,000 86,590,000 118,799,000 126,905,000 58,680,000 83,974,000 115,213,000 133,280,000 69,832,000 98,349,000 91,340,000 82,474,000 135,799,000 148,157,000 45,314,000 48,993,000 65,443,000 67,075,000 21,736,000 39,332,000 54,910,000 29,023,000 11,572,000 24,151,000 36,369,000 36,244,000 976,000 16,431,000 31,089,000   84,194,000 12,058,000   -12,713,000 -10,255,000 3,966,000 -20,871,000 568,000 40,228,000 10,395,000 -7,089,000 27,377,000 -93,337,000 28,672,000 8,960,000 26,801,000 35,361,000 22,902,000 10,502,000 61,874,000 12,359,000 23,426,000 32,015,000 38,233,000 37,133,000 29,156,000 22,730,000 38,827,000 57,929,000 10,430,000 9,185,000 8,624,000 4,955,000 14,628,000 15,987,000 8,922,000 12,940,000 11,188,000 3,501,000 
          adjustments to reconcile net income to net cash from operating activities:
                                                                               
          depreciation and amortization
        115,799,000 103,012,000 114,729,000 116,285,000 111,980,000 105,290,000 100,063,000 100,504,000 95,065,000 98,336,000 92,970,000 87,034,000 88,394,000 87,868,000 84,298,000 82,929,000 71,451,000 71,592,000 72,163,000 71,418,000 74,470,000 72,494,000 74,533,000 77,397,000 73,756,000 74,217,000 75,355,000 77,939,000 73,082,000 72,760,000 74,844,000 71,490,000 72,989,000 71,531,000 72,412,000 71,347,000 73,360,000 73,393,000 68,902,000 69,005,000 69,060,000 67,773,000 68,356,000 70,603,000 70,049,000 66,075,000 69,356,000 67,545,000 69,430,000 67,468,000 60,006,000 44,852,000 41,300,000 38,663,000 36,831,000 35,663,000 34,604,000 26,936,000 25,460,000 22,892,000 22,105,000 22,674,000 18,649,000 12,241,000 12,061,000 11,414,000 10,806,000 10,475,000 9,814,000 9,049,000 8,938,000 
          allowance for doubtful accounts
        2,919,000 1,559,000 3,271,000 424,000 2,825,000 2,455,000 1,325,000 2,621,000 1,728,000 3,336,000 1,411,000 1,099,000 -243,000 3,308,000 3,619,000 832,000 5,077,000 -337,000 2,446,000 -308,000 1,435,000 4,306,000 4,700,000 3,153,000 1,488,000 1,192,000 -3,425,000 8,948,000 -520,000 5,086,000 2,303,000 2,266,000 2,055,000 1,645,000 1,935,000 704,000 2,975,000 2,156,000 1,072,000 -838,000 1,095,000 2,332,000 2,204,000 2,174,000 2,138,000 2,519,000 2,086,000 2,652,000 1,663,000 1,795,000 1,823,000 404,000 404,000 202,000 203,000  221,000 197,000 205,000 -670,000 314,000 519,000 145,000 167,000 502,000 17,000      
          amortization of deferred financing costs and debt discount
        1,307,000 1,293,000 1,672,000 1,686,000 1,666,000 1,698,000 1,686,000 1,608,000 1,329,000 1,273,000 1,318,000 1,567,000 1,599,000 1,574,000 1,561,000 1,527,000 912,000 906,000 900,000 978,000 901,000 896,000 891,000 901,000 908,000 1,000,000 1,000,000 1,005,000 960,000 965,000 916,000 920,000 902,000 831,000 829,000 852,000 913,000 900,000 872,000 821,000 820,000 820,000 819,000 832,000 881,000 752,000 824,000 762,000 847,000 846,000 846,000 620,000 420,000 386,000 367,000  332,000 284,000 614,000 746,000 743,000 732,000 495,000 424,000 366,000 441,000 467,000 609,000 461,000 527,000 474,000 
          accretion of environmental liabilities
        3,542,000 3,616,000 3,499,000 3,591,000 3,620,000 3,317,000 3,618,000 3,304,000 3,217,000 3,386,000 3,388,000 3,344,000 3,246,000 3,197,000 3,156,000 3,120,000 2,799,000 2,873,000 2,953,000 2,902,000 2,822,000 2,766,000 2,561,000 2,512,000 2,490,000 2,560,000 2,574,000 2,478,000 2,450,000 2,448,000 2,430,000 2,407,000 2,347,000 2,416,000 2,290,000 2,648,000 2,476,000 2,548,000 2,505,000 2,607,000 2,577,000 2,599,000 2,619,000 2,637,000 2,642,000 2,609,000 2,724,000 2,913,000 2,914,000 2,879,000 2,835,000 2,508,000 2,488,000 2,505,000 2,416,000 2,449,000 2,435,000 2,407,000 2,389,000 2,495,000 2,602,000 2,702,000 2,644,000 2,634,000 2,650,000 2,682,000 2,726,000 2,670,000 2,715,000 2,554,000 2,474,000 
          changes in environmental liability estimates
        -1,635,000 -1,175,000 21,000 909,000 -9,863,000 -208,000 384,000 3,046,000 917,000 1,570,000 2,871,000 6,167,000 873,000 920,000 312,000 2,638,000 -104,000 170,000 275,000 1,648,000 3,443,000 2,137,000 3,470,000 253,000 163,000 26,000 -774,000 2,448,000 372,000 -111,000 -562,000 117,000 -183,000 -231,000 102,000 -3,905,000 -34,000 -220,000 -95,000 -9,145,000 -3,087,000 502,000 385,000 -376,000 -1,562,000 -608,000 -821,000 -1,265,000 -2,024,000 -335,000 -58,000 -4,905,000 -458,000 -2,449,000 -646,000                 
          other expense
        731,000 -3,218,000 -3,517,000 603,000 932,000 -977,000 1,123,000 167,000 1,141,000 -3,148,000  -399,000 -104,000 -1,265,000 -704,000 -1,994,000 -199,000 1,480,000 1,228,000 -307,000 -2,268,000 500,000 2,365,000 -905,000   -2,983,000 4,061,000 996,000 -846,000 299,000 3,305,000 432,000 833,000 1,549,000 -6,932,000                                    
          stock-based compensation
        9,578,000 10,082,000 8,922,000 6,063,000 7,635,000 7,291,000 5,837,000 8,515,000 6,338,000 5,894,000 4,291,000 6,469,000 7,828,000 6,835,000 5,712,000 6,053,000 6,001,000 3,305,000 3,480,000 5,763,000 6,662,000 2,786,000 3,291,000 3,152,000 5,021,000 3,834,000 5,809,000 6,066,000 4,087,000 3,562,000 3,077,000 3,934,000 4,040,000 2,901,000 2,271,000 2,746,000 2,996,000 2,646,000 2,093,000 2,000,000 404,000 4,296,000 1,850,000 2,354,000 2,106,000 2,062,000 2,278,000 2,557,000 2,465,000 2,037,000 1,887,000 2,259,000 1,619,000 1,475,000 2,141,000  2,449,000 1,136,000 1,744,000 2,113,000 2,316,000 791,000   762,000 997,000 1,052,000 733,000 936,000 1,073,000 894,000 
          environmental expenditures
        -4,086,000 -5,139,000 -3,909,000 -4,460,000 -2,591,000 -7,843,000 -9,745,000 -5,205,000 -4,729,000 -4,896,000 -7,741,000 -4,226,000 -2,692,000 -3,413,000 -3,615,000 -3,283,000 -5,629,000 -3,583,000 -3,011,000 -3,585,000 -2,712,000 -2,669,000 -3,435,000 -5,897,000 -6,670,000 -2,870,000 -3,264,000 -2,877,000 -2,653,000 -2,160,000 -2,425,000 -2,887,000 -3,976,000 -3,164,000 -2,938,000 -2,796,000 -2,920,000 -2,936,000 -3,518,000 -3,357,000 -5,241,000 -5,928,000 -5,604,000 -8,115,000 -4,687,000 -3,257,000 -4,186,000 -3,488,000 -6,135,000 -4,502,000 -5,291,000 -3,358,000 -4,046,000 -2,065,000 -1,722,000                 
          changes in assets and liabilities, net of acquisitions:
                                                                               
          accounts receivable and unbilled accounts receivable
        -104,781,000 81,282,000 3,268,000 -41,823,000 -74,576,000 116,825,000 -29,340,000 -71,924,000 -44,383,000 48,898,000 -40,786,000 92,475,000 -29,978,000 -124,894,000 -138,690,000 17,050,000 -62,316,000 -41,582,000 -9,703,000 -1,547,000 -43,571,000 92,500,000 -24,960,000 -1,863,000 -18,124,000 -25,370,000 12,086,000 -3,314,000 -13,485,000 -47,995,000 -14,769,000 4,358,000 -6,968,000 -55,455,000 24,301,000  -33,937,000 -34,846,000 35,839,000  69,809,000 -160,096,000 27,065,000                             
          inventories and supplies
        7,803,000 4,160,000 5,349,000 -5,718,000 8,670,000 -9,915,000 -11,000,000 -15,101,000 -13,572,000 -17,003,000 13,802,000 -30,223,000 -20,436,000 -10,278,000 -13,610,000 -18,807,000 -13,647,000 1,512,000 -747,000 1,621,000 -530,000 -2,000,000 -7,024,000 -3,887,000 -7,853,000 -3,297,000 -832,000 -6,424,000 -1,909,000 -13,000,000 -5,625,000 -27,000 1,332,000 -3,631,000 -2,676,000 -2,358,000 -12,609,000 1,769,000 -2,882,000 -649,000 -2,986,000 -4,437,000 22,131,000 -664,000 -11,119,000 -7,847,000 -1,709,000 -2,854,000 582,000 -12,445,000 13,573,000                     
          other current and non-current assets
        7,513,000        -25,918,000 -4,455,000 4,559,000 -4,703,000 12,904,000 7,420,000 -32,924,000 20,053,000 1,258,000 -2,087,000 -9,956,000 6,718,000 6,520,000 -34,554,000 8,714,000  5,281,000 1,032,000 -11,738,000                                             
          accounts payable
        -40,814,000 58,874,000 543,000 -25,046,000 -10,989,000 -17,677,000 42,422,000 4,940,000 -17,358,000 12,588,000 38,126,000 21,481,000 7,231,000 2,747,000 43,001,000 21,424,000 37,094,000 27,701,000 22,179,000 -16,430,000 18,236,000 -76,965,000 -5,169,000 4,118,000 23,950,000 7,041,000 -27,956,000 24,874,000 -1,564,000 13,891,000 9,714,000 -3,599,000 -4,399,000 10,923,000 -13,609,000 8,448,000 -3,554,000 27,798,000 -36,195,000 -63,350,000 -61,588,000 106,016,000 2,623,000 1,326,000 -6,931,000 -23,047,000 -23,374,000 -140,000 70,683,000 -17,314,000 -16,112,000 24,899,000 -2,065,000 -12,602,000 -4,302,000     -583,000            
          other current and long-term liabilities
        -54,780,000 17,798,000 41,412,000 35,033,000 -89,401,000 9,876,000 36,939,000 53,242,000 -54,970,000 21,173,000 14,904,000 -9,632,000 21,151,000 57,287,000 -38,285,000 956,000 -8,636,000 31,456,000 -904,000 14,710,000 23,510,000 48,401,000 -40,902,000 26,125,000 22,217,000 14,193,000 -17,088,000 -17,264,000 22,803,000 9,322,000 -2,740,000 -18,058,000 17,605,000 15,821,000 -6,873,000 -25,711,000 33,540,000 16,304,000 -10,283,000 -81,360,000 3,118,000 53,367,000 -29,528,000 -32,713,000 17,100,000 33,236,000 -20,573,000 -18,091,000 11,047,000 29,793,000 -21,128,000 -58,299,000 4,221,000                   
          net cash from operating activities
        6,297,000 355,093,000 301,987,000 208,040,000 1,605,000 303,938,000 239,239,000 216,045,000 18,549,000 278,860,000 220,119,000 268,672,000 225,572,000   177,771,000 102,794,000 162,432,000 103,000,000 113,165,000 143,946,000 139,805,000 33,681,000 128,517,000 146,205,000 108,730,000 29,740,000 125,995,000 117,545,000 77,767,000 51,903,000 64,229,000 104,538,000 59,812,000 57,119,000 80,797,000 58,776,000 80,762,000 39,289,000 86,790,000 115,778,000 109,038,000 84,777,000 101,327,000 81,095,000 110,348,000 4,596,000 135,725,000 142,502,000 98,023,000 39,589,000 91,673,000 56,918,000 146,221,000 29,553,000 28,195,000 75,707,000 60,773,000 14,856,000 56,613,000   17,472,000 37,146,000 11,911,000 33,952,000 29,265,000 13,016,000 34,455,000   
          capital expenditures
        -98,443,000 -121,749,000 -94,445,000 -90,029,000 -118,695,000 -62,415,000 -96,803,000 -135,110,000 -137,913,000 -110,394,000 -107,608,000 -100,509,000 -96,505,000   -95,202,000 -54,666,000 -50,075,000 -41,913,000 -45,899,000 -24,636,000 -42,954,000 -82,767,000 -41,791,000 -56,161,000 -59,425,000 -58,947,000 -42,622,000 -56,583,000 -49,897,000 -44,242,000 -39,271,000 -38,994,000 -46,280,000 -42,462,000 -44,036,000 -51,819,000 -47,748,000 -75,781,000 -67,197,000 -65,854,000 -71,196,000 -52,949,000 -58,736,000 -60,691,000 -63,181,000 -75,005,000 -72,566,000 -66,175,000 -69,217,000 -72,249,000 -67,071,000 -47,355,000 -55,310,000 -27,661,000     
          free cash flows
        -92,146,000 233,344,000 207,542,000 118,011,000 -117,090,000 241,523,000 142,436,000 80,935,000 -119,364,000 168,466,000 112,511,000 168,163,000 129,067,000   82,569,000 48,128,000 112,357,000 61,087,000 67,266,000 119,310,000 96,851,000 -49,086,000 86,726,000 90,044,000 49,305,000 -29,207,000 83,373,000 60,962,000 27,870,000 7,661,000 24,958,000 65,544,000 13,532,000 14,657,000 36,761,000 6,957,000 33,014,000 -36,492,000 19,593,000 49,924,000 37,842,000 31,828,000 42,591,000 20,404,000 47,167,000 -70,409,000 63,159,000 76,327,000 28,806,000 -32,660,000 24,602,000 9,563,000 90,911,000 1,892,000 28,195,000 75,707,000 60,773,000 14,856,000 56,613,000   17,472,000 37,146,000 11,911,000 33,952,000 29,265,000 13,016,000 34,455,000   
          cash flows from investing activities:
                                                                               
          additions to property, plant and equipment
        -98,443,000 -121,749,000 -94,445,000 -90,029,000 -118,695,000 -62,415,000 -96,803,000 -135,110,000 -137,913,000 -110,394,000 -107,608,000 -100,509,000 -96,505,000 -77,734,000 -70,308,000 -95,202,000 -54,666,000 -50,075,000 -41,913,000 -45,899,000 -24,636,000 -42,954,000 -82,767,000 -41,791,000 -56,161,000 -59,425,000 -58,947,000 -42,622,000 -56,583,000 -49,897,000 -44,242,000 -39,271,000 -38,994,000 -46,280,000 -42,462,000 -44,036,000 -51,819,000 -47,748,000 -75,781,000 -67,197,000 -65,854,000 -71,196,000 -52,949,000 -58,736,000 -60,691,000 -63,181,000 -75,005,000 -72,566,000 -66,175,000 -69,217,000 -72,249,000 -67,071,000 -47,355,000 -55,310,000 -27,661,000                 
          proceeds from sale and disposal of fixed assets
        1,522,000 6,318,000 11,187,000 2,720,000 1,343,000 2,746,000 2,058,000 3,287,000 1,008,000 4,521,000 2,185,000 3,661,000 2,095,000 1,703,000 1,320,000 5,732,000 12,945,000 2,275,000 1,204,000 2,316,000 4,206,000 951,000 2,150,000 2,707,000 1,559,000 3,068,000 4,321,000 9,334,000 3,470,000 1,843,000 798,000 1,749,000                                        
          acquisition, net of cash acquired
        -131,820,000                                                                       
          additions to intangible assets including costs to obtain or renew permits
        -159,000 -2,120,000 -751,000 -529,000 -248,000 -7,062,000 -677,000 -1,334,000 -534,000 -1,142,000 -393,000 -872,000 -258,000 -515,000 -321,000 -1,189,000 -909,000 -1,245,000 -505,000 -166,000 -621,000 -794,000 -448,000 -1,008,000 -973,000 -791,000 -1,132,000                                             
          purchases of available-for-sale securities
        -16,142,000 -54,573,000 -16,486,000 -21,436,000 -24,186,000 -44,179,000 -18,364,000 -24,090,000 -31,228,000 -53,935,000 -29,878,000 -13,427,000 -13,236,000 -18,180,000 -5,002,000 -32,449,000 -7,096,000 -46,709,000 -42,980,000 -17,494,000 -7,847,000 -13,492,000 -32,058,000 -5,075,000 -6,760,000 -11,060,000 -12,941,000 -24,301,000 -10,470,000 -6,998,000 -3,003,000                                        
          proceeds from sale of available-for-sale securities
        22,319,000 18,650,000 24,650,000 28,862,000 21,456,000 24,176,000 28,326,000 38,345,000 33,350,000 32,969,000 34,100,000 16,875,000 18,901,000 22,385,000 10,450,000 15,186,000 12,700,000 50,151,000 20,375,000 22,079,000 10,290,000 16,671,000 12,180,000 9,590,000 15,094,000 17,918,000 8,600,000 8,600,000 8,909,000 7,950,000 3,264,000                                         
          net cash from investing activities
        -222,723,000 -149,199,000 -75,845,000 -80,412,000 -120,330,000 -90,734,000 -82,270,000 -120,797,000 -609,873,000 -127,981,000 -99,804,000 -106,982,000 -94,480,000 -128,621,000 -58,861,000 -1,338,335,000 -36,927,000 -45,603,000 -86,737,000 -39,164,000 -18,611,000 -48,598,000 -93,087,000 -30,747,000 -47,241,000 -64,899,000 -74,969,000 -50,177,000 -83,341,000 -51,713,000 -164,428,000 -81,841,000 -71,056,000 1,498,000 -51,868,000 -27,938,000 -152,418,000 -71,408,000 -110,013,000 -80,140,000 -66,305,000 -150,837,000 -53,360,000 -67,598,000 -59,402,000 -68,960,000 -62,334,000 -77,745,000 -126,326,000 -69,191,000 -72,250,000 -1,346,219,000 -97,943,000 -92,714,000 -35,760,000 -34,571,000                
          cash flows from financing activities:
                                                                               
          change in uncashed checks
        -7,556,000 6,202,000 128,000 -1,053,000 -1,714,000 4,379,000 -3,984,000 -9,646,000 7,778,000 -245,000 612,000 -335,000 412,000 2,770,000 -2,295,000 2,517,000 -1,428,000 3,767,000 -6,662,000 5,023,000 2,070,000 86,000 -1,775,000 -189,000 -2,000 1,255,000 -4,769,000 3,608,000 -673,000 1,040,000 -3,843,000 2,717,000 -296,000 -804,000 -7,557,000 3,907,000 3,938,000 -5,804,000 -5,218,000 7,252,000 278,000 -1,892,000 -20,268,000 15,660,000 -3,753,000 3,141,000 21,000 2,514,000 -30,602,000 13,937,000 26,419,000 1,885,000 -4,459,000 4,080,000 -13,576,000  -16,326,000         -542,000 675,000 1,402,000    
          tax payments related to withholdings on vested restricted stock
        -9,303,000 -2,001,000 -3,377,000 -1,768,000 -8,688,000 -2,245,000 -6,915,000 -1,547,000 -3,052,000 -2,952,000 -6,551,000 -2,587,000 -3,643,000 -740,000 -1,831,000 -3,422,000 -2,644,000 -1,020,000 -3,719,000 -924,000 -1,012,000 -1,171,000 -2,224,000 -1,924,000 -525,000 -2,704,000 -2,276,000 -700,000 -391,000 -1,627,000 -548,000                                         
          repurchases of common stock
        -25,000,000 -133,001,000 -50,000,000 -12,001,000 -55,000,000 -24,963,000 -20,000,000 -5,215,000 -5,000,000 -33,164,000 -9,999,000 -6,001,000 -10,488,000 -30,000,000 -3,694,000 -6,001,000 -3,000,000 -18,863,000 -26,546,000 -35,302,000 -22,201,000 -17,341,000 -5,000,000 -5,118,000 -4,948,000 -6,324,000 -11,499,000 -7,099,000 -12,218,000 -14,264,000 -24,506,000 -12,208,000 -5,461,000 -6,796,000 -6,319,000 -5,735,000 -5,136,000 -4,998,000 -4,192,000 -36,952,000 -16,824,000 -15,379,000 -56,012,000 -33,672,000 -13,432,000 -1,225,000                         
          deferred financing costs paid
        -643,000     -638,000 -168,000 -3,507,000 -4,641,000 -365,000 -25,000 -89,000 -30,000 -291,000 -13,587,000 -4,000 -9,000 -137,000     -26,000    -89,000 -3,470,000   28,000 -1,019,000 -4,619,000 -108,000 -1,417,000 -424,000 -2,190,000         -58,000 -128,000 -2,318,000 -9,418,000 -9,617,000                   
          payments on finance leases
        -12,601,000 -8,025,000 -8,334,000 -6,673,000 -10,081,000 -7,290,000 -12,105,000 -6,826,000 -4,665,000 -4,343,000 -4,006,000 -3,283,000 -2,986,000 -2,967,000 -3,585,000 -2,613,000 -2,268,000 -1,905,000 -1,672,000 -1,714,000 -965,000 -1,461,000 -329,000                                                 
          principal payments on debt
        -3,150,000 -1,998,571,000 -3,776,000 -3,775,000 -3,776,000 -3,775,000 -3,776,000 -3,775,000 -3,776,000 -2,500,000 -2,500,000 -102,500,000 -4,384,000 -4,384,000 -4,384,000 -1,883,000 -1,884,000 -1,884,000 -1,884,000 -1,883,000 -1,884,000 -1,884,000 -1,884,000 -1,883,000 -846,884,000 -1,884,000 -1,884,000                                             
          net cash from financing activities
        -58,253,000     -31,523,000 -46,948,000 -30,516,000 486,019,000  -22,469,000  -21,178,000 -35,351,000 -16,080,000 970,011,000    -36,971,000 -98,992,000 -79,430,000 126,447,000 -9,293,000 -20,339,000 -8,425,000 -15,368,000    -19,655,000     -2,574,000 -2,353,000 -11,632,000 236,794,000  -36,893,000 -18,978,000 -37,194,000  -38,185,000 -14,558,000 -334,000 3,448,000 -30,341,000 14,385,000 25,634,000 961,779,000 266,343,000 3,545,000 -13,799,000 10,884,000 -17,685,000 16,955,000 248,586,000       -51,002,000 176,078,000 2,450,000    
          effect of exchange rate change on cash
        -3,642,000 4,038,000 -1,772,000 5,051,000 209,000 -6,860,000 358,000 -565,000 -1,568,000 1,423,000 -657,000 -3,404,000 -5,522,000 -1,580,000 579,000 -3,535,000 -3,550,000 2,276,000 1,639,000 6,365,000 1,997,000 3,384,000 -6,827,000 1,281,000 -847,000 1,678,000 1,461,000 -4,225,000 711,000 -1,065,000 -867,000 -1,058,000 1,683,000 1,552,000 554,000 -1,145,000 929,000 -144,000 4,567,000 -4,019,000 -7,010,000 659,000 -7,363,000 -4,003,000 -4,131,000 2,807,000 -2,994,000 10,000 -678,000 -1,843,000 -705,000 -1,011,000 1,538,000 -1,821,000 810,000  2,000 66,000 1,299,000   658,000 1,040,000      2,683,000 2,675,000 184,000 
          decrease in cash and cash equivalents
        -278,321,000   110,769,000 -197,775,000   64,167,000 -106,873,000  97,189,000    -112,991,000           37,084,000 -59,136,000    -133,047,000          5,570,000 -60,118,000 -13,140,000    -61,066,000    -7,732,000                     
          cash and cash equivalents, beginning of period
        826,315,000  687,192,000  444,698,000   452,575,000  519,101,000  371,991,000  226,507,000  319,399,000  306,997,000  184,708,000  246,879,000  310,073,000  229,836,000  260,723,000  302,210,000 233,546,000 249,524,000 119,538,000 73,550,000 
          cash and cash equivalents, end of period
        547,994,000  159,011,000 110,769,000 489,417,000  110,379,000 64,167,000 337,825,000  97,189,000  104,392,000 5,047,000 339,584,000  51,089,000 99,191,000 496,383,000  28,340,000 15,161,000 432,205,000  77,778,000 37,084,000 167,371,000  18,429,000 10,716,000 186,352,000  -84,708,000 149,000,000 297,366,000  -95,066,000 -2,422,000 355,345,000  5,570,000 -60,118,000 233,739,000  -20,623,000 29,637,000 249,007,000  -14,843,000 41,374,000 222,104,000  226,856,000 55,231,000 241,527,000  -120,417,000 -154,187,000 531,763,000 -14,384,000 88,696,000 206,604,000 -35,131,000 28,446,000 226,961,000 -28,934,000 195,740,000 86,153,000 14,500,000 19,408,000 57,948,000 
          supplemental information:
                                                                               
          cash payments for interest and income taxes:
                                                                               
          interest paid
        38,435,000 23,743,000 56,950,000 19,899,000 56,671,000 18,882,000 60,098,000 22,836,000 51,243,000 13,747,000 51,556,000 19,236,000 38,303,000 14,407,000 33,697,000 11,633,000 27,643,000 6,657,000 27,507,000 6,535,000 27,673,000 7,679,000 30,648,000 8,412,000 13,071,000 30,657,000 8,712,000 30,859,000 17,567,000 26,069,000 14,676,000 25,624,000 17,118,000 28,715,000 21,717,000 22,408,000 21,986,000 22,467,000 21,808,000 15,313,000 21,202,000 15,744,000 21,667,000 16,962,000 21,376,000 15,634,000 21,436,000 17,543,000 21,243,000 15,116,000 21,725,000 641,000 19,364,000 1,001,000 20,811,000  18,618,000 762,000 10,789,000 12,658,000 1,388,000 12,184,000 4,276,000 823,000 2,150,000 5,590,000 903,000 6,386,000 7,321,000 -1,845,000 5,680,000 
          income taxes paid, net of refunds
        7,916,000 24,373,000 28,997,000 55,254,000 9,280,000 29,854,000 30,445,000 62,287,000 8,020,000 24,986,000 14,834,000 25,343,000 23,876,000 26,186,000 3,121,000 16,990,000 15,683,000 28,920,000 3,599,000 38,928,000                                                    
          non-cash investing activities:
                                                                               
          property, plant and equipment accrued
        39,903,000 -3,272,000 11,448,000 12,694,000 12,462,000 146,000 15,289,000 49,000 28,266,000 23,249,000 2,700,000 7,224,000 2,570,000 9,759,000 11,397,000 7,703,000 2,754,000 3,699,000 5,108,000 -8,196,000 4,311,000 -4,752,000 12,173,000 16,089,000 772,000 1,101,000 13,002,000 1,823,000 793,000 -4,870,000 17,911,000 1,600,000 -1,704,000 -3,057,000 19,270,000 -8,967,000 -6,006,000 9,240,000 14,947,000 3,128,000 -5,250,000 11,967,000 22,832,000 -413,000 2,042,000 -4,781,000 26,715,000 -6,590,000 1,154,000 16,928,000 21,722,000 -2,190,000 5,093,000 7,119,000 19,766,000  -4,298,000 7,015,000 17,571,000 37,000 2,414,000 2,324,000 -1,575,000 1,204,000 3,558,000 1,061,000 -827,000 5,099,000 779,000 1,353,000 2,255,000 
          rou assets obtained in exchange for operating lease liabilities
        24,399,000  16,869,000 19,229,000 15,638,000  49,507,000 26,319,000 23,101,000  23,267,000  19,213,000 13,344,000 7,342,000  12,754,000 3,469,000 2,305,000  3,777,000 3,806,000 12,410,000                                                 
          rou assets obtained in exchange for finance lease liabilities
        4,592,000  2,135,000 30,621,000 27,181,000  8,217,000 30,655,000 14,519,000  12,325,000  3,617,000 2,967,000 4,679,000  9,499,000 9,205,000  11,881,000 17,308,000 -856,000                                                 
          deferred income taxes
             18,855,000 -330,000 -88,000 13,041,000 15,323,000 2,226,000 -3,720,000 3,290,000 1,951,000 -39,000     8,978,000 663,000   19,028,000 71,000 -5,000 -5,000 -83,519,000 -6,000 -6,000 196,000 44,010,000 -22,305,000 -6,528,000 7,000 20,924,000 -18,086,000 -5,000 -903,000 23,814,000 8,507,000   30,847,000 280,000 -40,000 32,000 34,657,000 16,000 -241,000 -269,000  -1,016,000 333,000 486,000 152,000            
          loss on early extinguishment of debt
                 518,000             12,000    19,000    1,846,000                                       
          gain on sale of businesses
                                                                               
          acquisitions, net of cash acquired
             -4,000,000 3,190,000 -1,895,000 -475,306,000 1,040,000 -12,710,000 -4,802,000 -73,766,000 5,000,000 -1,230,413,000 99,000 -22,918,000 38,000   116,000 -14,609,000 -14,870,000 -27,273,000 -3,750,000 -120,000,000 -4,795,000 -35,155,000 2,669,000 -11,946,000 174,000 -148,100,000 -23,996,000 -34,993,000 -14,735,000   -10,037,000   -3,806,000   -197,000 -1,281,446,000 -49,436,000 -34,288,000 -8,751,000                 
          proceeds from sale of businesses, net of transaction costs
                                                                               
          cash flows (used in) from financing activities:
                                                                               
          proceeds from employee stock purchase plan
         3,798,000                                         2,223,000 2,141,000 2,098,000 1,936,000 1,845,000 1,546,000 1,569,000 1,497,000 1,892,000 1,238,000  895,000 857,000 699,000 582,000 613,000 574,000 518,000 672,000 585,000 479,000 397,000 379,000 308,000 282,000 260,000 
          proceeds from issuance of debt, net of discount
             499,375,000                                                               
          borrowing from revolving credit facility
                          150,000,000                                                
          payment on revolving credit facility
                          -75,000,000                                                   
          net cash (used in) from financing activities
         -142,814,000 -65,359,000 -21,910,000 -79,259,000             -19,914,000 -40,620,000             -23,589,000   -15,436,000                                     
          increase in cash and cash equivalents
         67,118,000    174,821,000      43,580,000 104,392,000   -194,088,000 51,089,000 99,191,000 -22,718,000 43,395,000 28,340,000 15,161,000 60,214,000 89,758,000    11,010,000 18,429,000   -42,259,000 -84,708,000 149,000,000 -9,631,000 49,140,000 -95,066,000 -2,422,000 170,637,000     -11,142,000 -20,623,000   61,438,000 -14,843,000   -293,778,000 226,856,000 55,231,000 -19,196,000  -120,417,000 -154,187,000 229,553,000 -14,384,000      -28,934,000   14,500,000   
          cash and cash equivalents, beginning of year
                                                                               
          cash and cash equivalents, end of year
                                                                               
          other current and long-term assets
          7,928,000 -6,412,000 -6,983,000  -18,956,000                                                                 
          proceeds from sale of business
                                                                              
          gain on sale of business
                                       77,000   -453,000                                    
          proceeds from sale of business, net of transaction costs
                750,000   -675,000                                                           
          remedial liability assumed in acquisition of property, plant and equipment
                   -4,981,000 13,073,000                                                         
          proceeds from issuance of debt
                                                                              
          other income
                                             699,000 350,000 990,000 139,000 660,000 -409,000 -244,000 -613,000 655,000 -4,178,000 325,000 150,000 -1,655,000 -525,000 337,000 91,000 75,000 299,000 8,979,000   455,000             
          cash flows used in investing activities:
                                                                               
          cash flows used in financing activities:
                                                                               
          loss on sale of businesses
                           118,000 184,000 3,074,000                                                 
          proceeds from sale of businesses, net of transactional costs
                           -41,000 -103,000 7,856,000                                                 
          borrowings from revolving credit facility
                                                                               
          payments on revolving credit facility
                                                                               
          cash flows (used in) from operating activities:
                                                                               
          adjustments to reconcile net income to net cash (used in) from operating activities:
                                                                               
          net cash (used in) from operating activities
                      -38,629,000                                                         
          premiums paid on early extinguishment of debt
                               -12,000    -19,000    -1,363,000                                       
          payable for estimated purchase price adjustment
                                                                               
          issuance of unsecured senior notes
                                                                               
          income taxes paid
                             507,000 971,000 3,238,000 11,100,000 11,730,000 967,000 3,965,000 1,953,000 12,119,000 1,999,000 4,361,000 914,000 7,888,000 5,519,000 2,059,000 3,324,000 18,024,000 5,848,000 20,694,000    20,285,000 7,433,000 8,915,000 5,389,000  1,111,000 3,613,000 3,662,000 7,601,000 1,359,000 3,169,000 1,050,000  8,540,000 18,271,000 8,274,000 28,968,000 6,094,000 4,751,000 6,882,000 168,000 4,741,000 7,975,000 12,996,000 9,568,000 1,645,000 2,434,000 5,789,000 
          other current assets
                                   -7,423,000 -703,000 3,103,000 -2,923,000 -1,585,000 4,387,000 15,195,000 -1,277,000 -13,655,000 10,408,000 -6,627,000 1,838,000 30,054,000 19,522,000 -1,190,000 374,000 -8,982,000 7,526,000 12,958,000 -30,532,000 8,519,000 6,833,000 -1,350,000 6,377,000 4,204,000 -10,527,000 17,547,000 -1,890,000    2,949,000       -1,476,000      
          proceeds from exercise of stock options
                                       46,000 397,000 46,000         1,000 2,000 397,000 57,000 133,000 68,000 30,000  306,000 744,000 39,000 232,000 237,000 81,000 193,000 70,000 67,000 535,000 483,000 731,000 110,000 453,000 740,000 
          transfer of inventory to property, plant and equipment
                                                     11,369,000                     
          changes in assets and liabilities, net of acquisitions
                                                                               
          payments on finance lease
                                -68,000 -144,000 -115,000                                             
          issuance of secured senior notes, net of discount
                                                                               
          cash paid for amounts included in the measurement of lease liabilities:
                                                                               
          operating cash flows from operating leases
                                14,332,000 14,219,000 13,554,000                                             
          operating cash flows from finance lease
                                367,000 291,000 321,000                                             
          financing cash flows from finance lease
                                68,000 144,000 115,000                                             
          rou assets obtained in exchange for new operating lease liabilities
                                2,433,000 9,471,000 -3,896,000                                             
          rou assets obtained in exchange for new finance lease liabilities
                                                                               
          rou asset obtained in exchange for new finance lease liability
                                 23,027,000                                             
          goodwill impairment charge
                                                                            
          excess tax benefit of stock-based compensation
                                           -1,177,000 -19,000   31,000 -97,000 -5,000 -49,000 -185,000 -527,000 -117,000 180,000 -263,000 -99,000 -1,227,000 -770,000 -664,000 -409,000 -713,000  -3,566,000 512,000 1,105,000 439,000 631,000 151,000 351,000 47,000 18,000 798,000 994,000 1,604,000    
          net tax benefit on stock-based awards
                                                                               
          issuance of senior secured notes, net of discount
                                                                            
          issuance of senior unsecured notes, including premium
                                                                               
          (payable) receivable for estimated purchase price adjustment
                                                                               
          additions to intangible assets, including costs to obtain or renew permits
                                    -1,394,000 -861,000 -1,245,000  -109,000 -488,000 -751,000  -947,000 -461,000 -512,000  -1,545,000 -1,917,000 -1,171,000  -2,552,000 -1,816,000 -1,075,000  -2,188,000 -1,444,000 -725,000  -1,456,000 -528,000 -425,000                 
          principal payment on debt
                                    -401,884,000 -1,000,000 -1,000,000  -104,798,000                                       
          net loss
                                      -12,631,000    -21,393,000                                     
          adjustments to reconcile net loss to net cash from operating activities:
                                                                               
          receivable for estimated purchase price adjustment
                                          1,972,000   250,000 -1,518,000                               
          goodwill impairment charges
                                                                               
          net tax benefit (deficiency) on stock-based awards
                                                                               
          proceeds on sale of businesses, net of transactional costs
                                       -913,000 -52,000                                       
          proceeds from sale of investments
                                       133,000 243,000                                     
          payments on capital leases
                                               -11,000 -29,000 -73,000 -398,000 -440,000 -492,000 -552,000 -638,000 -795,000 -1,508,000 -1,242,000 -1,346,000 -1,296,000 -1,470,000 -1,667,000 -2,166,000                 
          net tax deficiency on stock based awards
                                            -39,000 -258,000 -345,000                                 
          issuance of restricted shares, net of shares remitted
                                        -189,000 -1,111,000 -1,021,000 -319,000 -621,000 -454,000 -1,425,000  -190,000 -683,000 -1,154,000                             
          non-cash investing and financing activities:
                                                                               
          accrual for repurchased shares
                                                  736,000                             
          proceeds from sales of fixed assets
                                         1,091,000 1,030,000 16,835,000 1,314,000 1,395,000 1,273,000 2,455,000 1,094,000 1,886,000 760,000 2,251,000 2,927,000 2,110,000 876,000 999,000 1,506,000 1,273,000 921,000  304,000 3,461,000 425,000    1,013,000   828,000          
          proceeds on sale of business
                                          2,018,000                                     
          issuance of senior secured notes, including premium
                                            250,625,000                  261,250,000             
          changes in assets and liabilities:
                                                                               
          accounts receivable and unbilled accounts receivables
                                                                               
          purchase of available-for-sale securities
                                                                               
          proceeds on sale of business, net of cash
                                                                              
          proceeds from sales of investments
                                                                               
          repayment of long-term obligations
                                                                             
          accrued business combination adjustments
                                                                               
          cash flows from (used in) financing activities:
                                                                               
          pre-tax, non-cash acquisition accounting inventory adjustments
                                                                               
          other
                                                           5,120,000                 
          remittance of shares
                                                   -125,000 -453,000 -1,465,000 -750,000 -132,000 -430,000 -128,000 -41,000 -1,308,000 -388,000                   
          issuance costs related to issuances of common stock
                                                                               
          net tax (deficiency) benefit on stock based awards
                                                -6,000                               
          proceeds from sales of marketable securities
                                                    77,000 12,870,000          37,000 388,000             
          income taxes (received) paid
                                                 6,858,000 -3,790,000                             
          net tax benefit on stock based awards
                                                  -111,000                             
          write-off of deferred financing costs and debt (premium) discount
                                                                               
          purchase of marketable securities
                                                                             
          proceeds from issuance of common stock
                                                                         -29,000      
          distribution of cash earned on employee participation plan
                                                           -17,000 -38,000                 
          issuance of senior unsecured notes, at par
                                                           600,000,000                    
          assets acquired through capital lease
                                                                               
          income tax benefit related to stock option exercises
                                                    185,000 527,000 117,000 -180,000 263,000 100,000 1,216,000 770,000 655,000 408,000 713,000  332,000 512,000 1,105,000 438,000 626,000 151,000 351,000 42,000 17,000       
          issuance costs related to 2012 issuance of common stock
                                                        -250,000                     
          accounts receivable
                                                     -4,430,000 3,741,000 18,642,000 -51,594,000 7,943,000 -28,726,000 -5,508,000 5,764,000 67,072,000 -12,955,000  -50,733,000      -25,266,000 2,897,000 25,212,000 -1,880,000 -4,707,000 15,077,000   10,586,000 
          payable for repurchased shares
                                                                               
          proceeds from sale of long-term investments
                                                                              
          accrued working capital adjustments
                                                                               
          pre-tax, non-cash acquisition accounting adjustments
                                                        13,559,000                     
          write-off of deferred financing costs and debt premium
                                                                               
          gains on sale of businesses
                                                                               
          proceeds from sales of fixed assets and assets held for sale
                                                                1,034,000   369,000   164,000 88,000 50,000 384,000 58,000 7,000 61,000 302,000 140,000 
          purchase of investment securities
                                                                               
          proceeds from insurance settlement
                                                                              
          issuance of acquisition-related common stock
                                                                               
          write-off deferred financing costs and debt premium
                                                                               
          other current liabilities
                                                              -22,935,000     -5,928,000         9,465,000   
          purchase of available for sale securities
                                                              -4,468,000                 
          income statement data:
                                                                               
          revenues
                                                                               
          cost of revenues
                                                                               
          selling, general and administrative expenses
                                                                               
          income from operations
                                                                               
          interest expense
                                                                               
          income from continuing operations before benefit from income taxes
                                                                               
          benefit from income taxes
                                                                               
          income from continuing operations
                                                                               
          income from discontinued operations, net of tax
                                                                               
          dividends on series b preferred stock
                                                                               
          net income attributable to common stockholders
                                                                               
          basic earnings attributable to common stockholders
                                                                               
          diluted earnings attributable to common stockholder
                                                                               
          cash flow data:
                                                                               
          other financial data:
                                                                               
          adjusted ebitda
                                                                               
          balance sheet data:
                                                                               
          working capital
                                                                               
          goodwill
                                                                               
          total assets
                                                                               
          long-term obligations
                                                                               
          stockholders' equity
                                                                               
          gains on sales of businesses
                                                                               
          write-off deferred financing costs and debt discount
                                                                               
          write-off of deferred financing costs and debt discount
                                                                               
          proceeds from sale of marketable securities
                                                                   52,000            
          payment on acquired debt
                                                                               
          issuance of secured notes
                                                                               
          issuance of clean harbors common stock for eveready common shares
                                                                               
          costs to obtain or renew permits
                                                                               
          new capital lease additions
                                                                               
          issuance of common stock
                                                                               
          sales of marketable securities
                                                                         3,500,000 850,000    
          proceeds from exercise of warrants
                                                                               
          issuance of senior secured notes
                                                                               
          (gain) loss on sale of fixed assets and assets held for sale
                                                                          -59,000 104,000    
          liabilities assumed in acquisition
                                                                        3,901,000       
          income tax benefits related to stock option exercises
                                                                         807,000 1,008,000 1,610,000    
          gain on sale of fixed assets and assets held for sale
                                                                               
          prepayment penalty on early extinguishment of debt
                                                                               
          dividend payments on preferred stock
                                                                               
          effect of exchange rate changes on cash
                                                                               
          (decrease) in cash and cash equivalents
                                                                               
          changes in environmental estimates
                                                                               
          impairment of assets held for sale
                                                                               
          investment in joint venture
                                                                               
          gain on insurance settlement
                                                                               
          proceeds from sales of restricted investments
                                                                               
          proceeds from insurance claim
                                                                               
          sale of marketable securities
                                                                               
          proceeds from term loan to finance acquisition
                                                                               
          capital lease obligations
                                                                               
          acquisition costs, net of cash acquired
                                                                               
          deferred financing costs incurred
                                                                               
          shares remitted to settle employee tax obligations
                                                                               
          loss on sale of fixed assets and assets held for sale
                                                                              6,000 
          acquisition of ensco caribe, net of cash acquired
                                                                               
          net cash (used in) investing activities
                                                                               
          shares remitted to settle employees’ tax obligations
                                                                               
          amortization of deferred financing costs
                                                                               
          amortization of debt discount
                                                                               
          foreign currency gain on intercompany transactions
                                                                               
          unbilled accounts receivable
                                                                               
          deferred costs
                                                                               
          prepaid expenses and other current assets
                                                                               
          supplies inventories
                                                                               
          other assets
                                                                               
          deferred revenue
                                                                               
          accrued disposal costs
                                                                               
          other accrued expenses
                                                                               
          income taxes payable
                                                                               
          acquisition of teris llc
                                                                               
          cost to obtain or renew permits
                                                                               
          proceeds from sale of restricted investments
                                                                               
          new capital lease obligations
                                                                               
          acquisition related costs included in accounts payable
                                                                               
          liabilities assumed in connection with the teris llc acquisition