7Baggers

Northwest Natural Holding Company
(NYSE:NWN) 

NWN stock logo

Northwest Natural Holding Company, through its subsidiary, Northwest Natural Gas Company, provides regulated natural gas distribution services to residential, commercial, industrial, and transportation customers in Oregon and Southwest Washington. The company also owns and operates 20 Bcf of undergr...

Founded: 1859
Full Time Employees: 1,200
Sector: Utilities
Industry: Utilities-Regulated Gas
Utilities
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• Market Cap:
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At a glance:
Bull Thesis:
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Income Statements:
Quarterly
Annual
    Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 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 
                                  
      operating revenues
    		490,403,000 394,157,000 164,728,000 236,194,000 494,284,000 136,934,000 211,714,000 433,470,000 355,714,000 141,479,000 237,859,000 462,423,000 375,253,000 116,839,000 194,960,000 350,301,000 294,090,000 101,447,000 148,917,000 315,946,000 260,273,000 93,284,000 134,971,000 285,151,000 247,264,000 90,317,000 123,443,000 285,348,000 226,702,000 91,239,000 
      operating expenses:
    		                              
      cost of gas
    		158,149,000 118,654,000 39,428,000 64,503,000 172,991,000 38,902,000 72,970,000 175,717,000 142,475,000 49,180,000 102,433,000 205,749,000 168,222,000 36,105,000 79,720,000 145,588,000 113,645,000 25,266,000 41,193,000 112,210,000 89,266,000 23,741,000 41,210,000 108,538,000 91,744,000 22,603,000 35,107,000 105,457,000 79,822,000 25,538,000 
      operations and maintenance
    		83,109,000 87,832,000 76,785,000 79,065,000 83,683,000 63,940,000 64,950,000 73,614,000 73,606,000 61,524,000 66,819,000 71,817,000 63,262,000 50,745,000 53,175,000 57,485,000 54,660,000 47,329,000 50,047,000 52,191,000 45,873,000 41,352,000 43,983,000 48,921,000 46,337,000 40,886,000 39,486,000 51,482,000 41,578,000 37,569,000 
      environmental remediation
    		6,325,000 4,827,000 1,247,000 2,296,000 6,253,000 1,151,000 2,329,000 5,746,000 4,352,000 1,032,000 2,140,000 5,375,000 4,439,000 980,000 2,267,000 4,703,000 3,846,000 806,000 1,509,000 3,777,000 3,197,000 867,000 1,622,000 4,005,000 5,079,000 967,000 -2,656,000 8,947,000 3,599,000 1,022,000 
      general taxes
    		16,343,000 12,133,000 12,066,000 12,076,000 15,771,000 10,886,000 11,853,000 15,468,000 10,563,000 10,577,000 10,889,000 14,219,000 10,366,000 9,572,000 8,989,000 12,104,000 9,289,000 9,061,000 8,914,000 11,369,000 8,154,000 8,656,000 8,373,000 9,895,000 7,489,000 7,993,000 7,879,000 9,027,000 7,380,000 7,589,000 
      revenue taxes
    		18,100,000 14,808,000 5,669,000 8,283,000 19,405,000 5,275,000 9,211,000 18,244,000 14,921,000 5,523,000 9,185,000 19,042,000 15,789,000 4,437,000 8,240,000 13,360,000 12,514,000 3,891,000 5,671,000 12,664,000 10,539,000 3,555,000 4,454,000 11,743,000 10,369,000 3,534,000 4,496,000 11,926,000 9,351,000 3,522,000 
      depreciation
    		44,134,000 42,961,000 40,510,000 41,535,000 40,500,000 34,552,000 33,762,000 33,098,000 32,762,000 30,061,000 31,293,000 31,465,000 31,142,000 29,026,000 28,110,000 28,429,000               
      other operating expenses
    		1,375,000 1,193,000 1,446,000 1,225,000 1,327,000 1,560,000 933,000 1,756,000 1,868,000 1,159,000 1,257,000 1,248,000 806,000 901,000 920,000 994,000 1,103,000 1,047,000 815,000 932,000 1,455,000 767,000 551,000 928,000 1,119,000 593,000 646,000 892,000 1,070,000 625,000 
      total operating expenses
    		327,535,000 282,408,000 177,151,000 208,983,000 339,930,000 156,266,000 196,008,000 323,643,000 280,547,000 159,056,000 224,016,000 348,915,000 294,026,000 131,766,000 181,421,000 262,663,000 223,912,000 115,838,000 136,293,000 221,240,000 185,722,000 104,872,000 126,029,000 208,705,000 186,299,000 99,951,000 107,345,000 209,303,000 164,449,000 97,350,000 
      income from operations
    		162,868,000 111,749,000 -12,423,000 27,211,000 154,354,000 -19,332,000 15,706,000 109,827,000 75,167,000 -17,577,000 13,843,000 113,508,000 81,227,000 -14,927,000 13,539,000 87,638,000 70,178,000 -14,391,000 12,624,000 94,706,000 74,551,000 -11,588,000 8,942,000 76,446,000 60,965,000 -9,634,000 16,098,000 76,045,000 62,253,000 -6,111,000 
      yoy
    		5.52% -678.05% -179.10% -75.22% 105.35% 9.98% 13.46% -3.24% -7.46% 17.75% 2.25% 29.52% 15.74% 3.72% 7.25% -7.46% -5.87% 24.19% 41.18% 23.89% 22.28% 20.28% -44.45% 0.53% -2.07% 57.65%     
      qoq
    		45.74% -999.53% -145.65% -82.37% -898.44% -223.09% -85.70% 46.11% -527.64% -226.97% -87.80% 39.74% -644.16% -210.25% -84.55% 24.88% -587.65% -214.00% -86.67% 27.04% -743.35% -229.59% -88.30% 25.39% -732.81% -159.85% -78.83% 22.15% -1118.70%  
      other income
    		512,000 -1,953,000 929,000 -160,000  930,000 6,000 -1,134,000 4,627,000 5,004,000 6,618,000 1,606,000 295,000 1,636,000 226,000 -954,000 -4,204,000 -2,216,000 -2,597,000 -3,542,000 -4,042,000 -3,287,000 -3,040,000 -3,575,000 -4,054,000 -2,267,000 -2,768,000 -13,747,000 -2,462,000 -312,000 
      interest expense
    		33,352,000 32,192,000 30,435,000 30,491,000 29,395,000 19,060,000 19,311,000 20,531,000 19,890,000 19,406,000 18,974,000 18,296,000 17,091,000 13,054,000 11,580,000 11,522,000 11,157,000 11,175,000 11,028,000 11,126,000 10,713,000 9,165,000 12,706,000 10,468,000 10,878,000 10,948,000 10,654,000 10,205,000 10,008,000 9,006,000 
      income before income taxes
    		130,028,000 77,604,000 -41,929,000 -3,440,000 122,443,000 -37,462,000 -3,599,000 88,162,000 59,904,000 -31,979,000 1,487,000 96,818,000 64,431,000 -26,345,000 2,185,000 75,162,000 54,817,000 -27,782,000 -1,001,000 80,038,000 59,796,000 -24,040,000 -6,804,000 62,403,000 46,033,000 -22,849,000 2,676,000 52,093,000 49,783,000 -15,429,000 
      income tax expense
    		32,539,000 19,811,000 -12,039,000 -940,000 34,527,000 -10,295,000 -812,000 24,339,000 15,264,000 -8,292,000 243,000 25,147,000 16,495,000 -6,758,000 470,000 18,923,000 14,289,000 -7,127,000 -277,000 20,521,000 13,990,000 -5,363,000 -1,672,000 14,127,000 7,685,000 -4,343,000 625,000 8,675,000 13,000,000 -4,285,000 
      net income
    		97,489,000 57,793,000 -29,890,000 -2,500,000 87,916,000 -27,167,000 -2,787,000 63,823,000 44,640,000 -23,687,000 1,244,000 71,671,000 47,936,000 -19,587,000 1,715,000 56,239,000 40,528,000 -20,655,000 -724,000 59,517,000 52,047,000 -17,912,000 -4,852,000 47,498,000 36,740,000 -19,301,000 1,095,000 43,201,000 35,824,000 -11,794,000 
      yoy
    		10.89% -312.73% 972.48% -103.92% 96.94% 14.69% -324.04% -10.95% -6.88% 20.93% -27.46% 27.44% 18.28% -5.17% -336.88% -5.51% -22.13% 15.31% -85.08% 25.30% 41.66% -7.20% -543.11% 9.95% 2.56% 63.65%     
      qoq
    		68.69% -293.35% 1095.60% -102.84% -423.61% 874.78% -104.37% 42.97% -288.46% -2004.10% -98.26% 49.51% -344.73% -1242.10% -96.95% 38.77% -296.21% 2752.90% -101.22% 14.35% -390.57% 269.17% -110.22% 29.28% -290.35% -1862.65% -97.47% 20.59% -403.75%  
      other comprehensive income:
    		                              
      amortization of non-qualified employee benefit plan liability, net of taxes 33 and 25 for the three months ended march 31, 2026 and 2025, respectively
    		91,000                              
      unrealized gain on interest rate swaps, net of taxes (6) and 47 for the three months ended march 31, 2026 and 2025, respectively
    		30,000                              
      comprehensive income
    		97,610,000 59,568,000 -29,730,000 -2,327,000 87,961,000 -27,847,000 -2,462,000 64,047,000 42,570,000 -23,411,000 2,583,000 71,362,000 52,459,000 -19,385,000 1,912,000 56,436,000 41,350,000 -20,421,000 -503,000 59,738,000 49,372,000 -17,726,000 -4,692,000 47,658,000 34,217,000 -19,187,000 1,210,000 43,316,000 36,613,000 -11,640,000 
      average common shares outstanding:
    		                              
      basic
    		41,708,000 224,000 41,184,000 40,482,000 40,244,000 38,394,000 38,260,000 37,765,000 263,000 36,214,000 36,019,000 35,609,000 443,000 34,939,000 34,307,000 31,187,000 43,000 30,696,000 30,664,000 30,614,000 13,000 30,555,000 30,537,000 30,491,000 223,000 30,429,000 29,337,000 28,906,000 16,000 28,815,000 
      diluted
    		41,816,000 235,000 41,184,000 40,482,000 40,304,000 38,394,000 38,260,000 37,796,000 285,000 36,214,000 36,062,000 35,708,000 445,000 34,939,000 34,352,000 31,212,000 44,000 30,696,000 30,664,000 30,633,000 24,000 30,555,000 30,537,000 30,535,000 231,000 30,429,000 29,394,000 28,970,000 27,000 28,815,000 
      earnings per share of common stock:
    		                              
      basic
    		2.34 1.4 -0.73 -0.06 2.18 -0.71 -0.07 1.69 1.22 -0.65 0.03 2.01 1.39 -0.56 0.05 1.8 1.32 -0.67 -0.02 1.94 1.7 -0.59 -0.16 1.56 1.23 -0.63 0.04 1.49 1.24 -0.41 
      diluted
    		2.33 1.41 -0.73 -0.06 2.18 -0.71 -0.07 1.69 1.22 -0.65 0.03 2.01 1.4 -0.56 0.05 1.8 1.32 -0.67 -0.02 1.94 1.7 -0.59 -0.16 1.56 1.23 -0.63 0.04 1.49 1.24 -0.41 
      change in employee benefit plan liability, net of taxes of —and 58 for three months ended and — and 9 for the nine months ended september 30, 2025 and 2024, respectively
    		                              
      amortization of non-qualified employee benefit plan liability, net of taxes (1) and 54 for the three months ended and 49 and 155 for the nine months ended september 30, 2025 and 2024, respectively
    		 137,250 200,000                            
      unrealized gain on interest rate swaps, net of taxes 14 and 279 for the three months ended and 62 and 133 for the nine months ended september 30, 2025 and 2024, respectively
    		 -42,750 -40,000                            
      change in employee benefit plan liability, net of taxes of —and 115 for three months ended and — and 49 for the six months ended june 30, 2025 and 2024, respectively
    		                              
      amortization of non-qualified employee benefit plan liability, net of taxes 25 and 55 for the three months ended and 50 and 101 for the six months ended june 30, 2025 and 2024, respectively
    		   174,000                           
      unrealized gain on interest rate swaps, net of taxes — and 22 for the three months ended and 47 and 146 for the six months ended june 30, 2025 and 2024, respectively
    		   -1,000                           
      other expense
    		    -2,516,000                          
      change in employee benefit plan liability, net of taxes of — and (66) for the three months ended march 31, 2025 and 2024, respectively
    		                              
      amortization of non-qualified employee benefit plan liability, net of taxes 25 and 46 for the three months ended march 31, 2025 and 2024, respectively
    		    175,000                          
      unrealized gain on interest rate swaps, net of taxes 47 and (124) for the three months ended march 31, 2025 and 2024, respectively
    		    -130,000                          
      change in employee benefit plan liability, net of taxes of 58 and 9 for the three and nine months ended september 30, 2024, respectively
    		     -58,000                         
      amortization of non-qualified employee benefit plan liability, net of taxes of 54 and 37 for the three months ended and 155 and 111 for the nine months ended september 30, 2024 and 2023, respectively
    		     153,000                         
      unrealized gain on interest rate swaps, net of taxes of 279 and 62 for the three months ended and 133 and 359 for the nine months ended september 30, 2024 and 2023, respectively
    		     -775,000                         
      change in employee benefit plan liability, net of taxes of 115 and 49 for the three and six months ended june 30, 2024, respectively
    		      115,000                        
      amortization of non-qualified employee benefit plan liability, net of taxes of 55 and 37 for the three months ended and 101 and 74 for the six months ended june 30, 2024 and 2023, respectively
    		      152,000                        
      unrealized gain on interest rate swaps, net of taxes of 22 and 445 for the three months ended and 146 and 297 for the six months ended june 30, 2024 and 2023, respectively
    		      58,000                        
      change in employee benefit plan liability, net of taxes of (66) for the three months ended march 31, 2024
    		       -249,000                       
      amortization of non-qualified employee benefit plan liability, net of taxes of 46 and 37 for the three months ended march 31, 2024 and 2023, respectively
    		       127,000                       
      unrealized gain on interest rate swaps, net of taxes of (124) and 149 for the three months ended march 31, 2024 and 2023, respectively
    		       346,000                       
      amortization of non-qualified employee benefit plan liability, net of taxes of 37 and 73 for the three months ended and 111 and 215 for the nine months ended september 30, 2023 and 2022, respectively
    		        76,750 102,000                     
      unrealized gain on interest rate swaps, net of taxes of 62 and 359 for the three and nine months ended september 30, 2023, respectively
    		        249,750 174,000                     
      amortization of non-qualified employee benefit plan liability, net of taxes of 37 and 71 for the three months ended and 74 and 142 for the six months ended june 30, 2023 and 2022, respectively
    		          103,000                    
      unrealized gain on interest rate swaps, net of taxes of 445 and 297 for the three and six months ended june 30, 2023, respectively
    		          1,236,000                    
      amortization of non-qualified employee benefit plan liability, net of taxes of 37 and 71 for the three months ended march 31, 2023 and 2022, respectively
    		           102,000                   
      unrealized loss on interest rate swaps, net of taxes of 149 for the three months ended march 31, 2023
    		           -411,000                   
      amortization of non-qualified employee benefit plan liability, net of taxes of 73 and 80 for the three months ended and 215 and 240 for the nine months ended september 30, 2022 and 2021, respectively
    		            149,000 202,000                 
      amortization of non-qualified employee benefit plan liability, net of taxes of 71 and 80 for the three months ended and 142 and 160 for the six months ended june 30, 2022 and 2021, respectively
    		              197,000                
      amortization of non-qualified employee benefit plan liability, net of taxes of 71 and 80 for the three months ended march 31, 2022 and 2021, respectively
    		               197,000               
      depreciation and amortization
    		                28,855,000 28,438,000 28,144,000 28,097,000 27,238,000 25,934,000 25,836,000 24,675,000 24,162,000 23,375,000 22,387,000 21,572,000 21,649,000 21,485,000 
      net income from continuing operations
    		                40,528,000 -20,655,000 -724,000 59,517,000 45,806,000 -18,677,000 -5,132,000 48,276,000 38,348,000 -18,506,000 2,051,000 43,418,000 36,783,000 -11,144,000 
      income from discontinued operations, net of tax
    		                    6,241,000 765,000 280,000        
      amortization of non-qualified employee benefit plan liability, net of taxes of 80 and 66 for the three months ended and 240 and 182 for the nine months ended september 30, 2021 and 2020, respectively
    		                169,000 234,000             
      earnings from continuing operations per share of common stock:
    		                              
      basic
    		                1.32 -0.67 -0.02 1.94 1.5 -0.61 -0.17 1.58 1.28 -0.61 0.07 1.5 1.28 -0.39 
      diluted
    		                1.32 -0.67 -0.02 1.94 1.5 -0.61 -0.17 1.58 1.28 -0.61 0.07 1.5 1.27 -0.39 
      earnings from discontinued operations per share of common stock:
    		                              
      basic
    		                    0.2 0.02 0.01        
      diluted
    		                    0.2 0.02 0.01        
      amortization of non-qualified employee benefit plan liability, net of taxes of 80 and 58 for the three months ended and 160 and 116 for the six months ended june 30, 2021 and 2020, respectively
    		                  221,000            
      loss from discontinued operations, net of tax
    		                       -778,000 -1,608,000 -795,000 -956,000 -217,000 -959,000 -650,000 
      amortization of non-qualified employee benefit plan liability, net of taxes of 80 and 58 for the three months ended march 31, 2021 and 2020, respectively
    		                   221,000           
      loss from discontinued operations per share of common stock:
    		                              
      basic
    		                       -0.02 -0.05 -0.02 -0.03 -0.01 -0.04 -0.02 
      diluted
    		                       -0.02 -0.05 -0.02 -0.03 -0.01 -0.03 -0.02 
      amortization of non-qualified employee benefit plan liability, net of taxes of 66 and 43 for the three months ended and 182 and 125 for the nine months ended september 30, 2020 and 2019, respectively
    		                    126,500 186,000         
      amortization of non-qualified employee benefit plan liability, net of taxes of 58 and 41 for the three months ended and 116 and 82 for the six months ended june 30, 2020 and 2019, respectively
    		                      160,000        
      amortization of non-qualified employee benefit plan liability, net of taxes of 58 and 41 for the three months ended march 31, 2020 and 2019, respectively
    		                       160,000       
      amortization of non-qualified employee benefit plan liability, net of taxes of 43 and 55 for the three months ended and 125 and 166 for the nine months ended september 30, 2019 and 2018, respectively
    		                        86,000 114,000     
      amortization of non-qualified employee benefit plan liability, net of taxes of 41 and 56 for the three months ended and 82 and 111 for the six months ended june 30, 2019 and 2018, respectively
    		                          115,000    
      amortization of non-qualified employee benefit plan liability, net of taxes of 41 and 55 for the three months ended march 31, 2019 and 2018, respectively
    		                           115,000   
      amortization of non-qualified employee benefit plan liability, net of taxes of 55 and 98 for the three months ended and 166 and 275 for the nine months ended september 30, 2018 and 2017, respectively
    		                            115,250 154,000 
    Balance Sheets:
    Quarterly
    Annual
      Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 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 
                                    
        assets:
      		                              
        current assets:
      		                              
        cash and cash equivalents
      		34,945,000 36,673,000 32,203,000 102,579,000 100,050,000 35,047,000 65,192,000 72,375,000 32,920,000 156,616,000 137,759,000 140,821,000 29,270,000 108,556,000 17,209,000 24,325,000 265,000 19,502,000 20,084,000 17,907,000 30,168,000 35,926,000 137,057,000 471,079,000 119,000 10,522,000 60,885,000 12,817,000 4,011,000 29,965,000 
        accounts receivable
      		150,545,000 121,875,000 70,507,000 78,865,000 154,746,000 53,123,000 61,821,000 128,433,000 121,341,000 51,999,000 73,930,000 164,157,000 168,906,000 50,850,000 68,583,000 103,131,000  39,209,000 60,713,000 105,226,000 88,083,000 40,278,000 35,196,000 78,083,000  29,617,000 42,670,000 93,617,000  25,125,000 
        accrued unbilled revenue
      		61,236,000 97,238,000 29,148,000 27,943,000 59,936,000 23,818,000 22,863,000 57,905,000 83,138,000 24,626,000 21,924,000 59,542,000 89,048,000 16,857,000 18,060,000 41,772,000  16,809,000 13,592,000 41,907,000 57,949,000 14,787,000 15,393,000 41,871,000  17,934,000 14,840,000 36,147,000  16,351,000 
        allowance for uncollectible accounts
      		-4,510,000 -4,068,000 -2,618,000 -3,210,000 -4,427,000 -2,885,000 -3,758,000 -4,181,000 -3,455,000 -2,312,000 -3,297,000 -6,760,000 -3,296,000 -2,171,000 -1,356,000 -2,488,000  -2,702,000 -3,283,000 -3,503,000 -3,219,000 -1,786,000 -1,592,000 -1,335,000  -180,000 -814,000 -1,301,000  -394,000 
        regulatory assets
      		146,545,000 143,745,000 140,502,000 103,914,000 88,623,000 136,275,000 124,102,000 127,666,000 178,270,000 108,525,000 111,819,000 126,546,000 117,491,000 104,830,000 92,803,000 64,481,000  80,638,000 60,672,000 47,789,000 31,745,000 29,740,000 30,021,000 37,815,000  47,996,000 46,688,000 46,317,000  41,241,000 
        derivative instruments
      		2,719,000 3,922,000 5,031,000 7,210,000 4,363,000 8,948,000 8,033,000 5,746,000 11,380,000 23,454,000 12,423,000 8,507,000 194,412,000 62,710,000 60,652,000 84,438,000  105,175,000 46,168,000 19,914,000 13,678,000 24,094,000 5,996,000 2,257,000  5,987,000 2,186,000 7,890,000  2,871,000 
        inventories
      		134,745,000 127,697,000 118,589,000 113,720,000 90,334,000 108,651,000 107,332,000 99,874,000 112,571,000 94,585,000 67,502,000 41,392,000 87,096,000 98,725,000 65,983,000 33,377,000  59,997,000 39,024,000 26,237,000 42,691,000 45,082,000 44,009,000 34,390,000  41,230,000 23,100,000 19,540,000  53,064,000 
        other current assets
      		57,895,000 75,850,000 42,199,000 35,095,000 46,275,000 45,873,000 37,535,000 49,896,000 65,275,000 49,947,000 35,797,000 41,968,000 61,286,000 41,414,000 36,060,000 42,329,000 11,348,000 33,285,000 22,427,000 30,656,000 44,741,000 25,534,000 20,318,000 26,460,000 4,600,000 18,617,000 18,296,000 20,293,000 3,078,000 20,376,000 
        total current assets
      		584,120,000 602,932,000 435,561,000 466,116,000 539,900,000 408,850,000 423,120,000 537,714,000 601,440,000 507,440,000 457,857,000 576,173,000 744,213,000 481,771,000 357,994,000 391,365,000 13,793,000 358,179,000 273,841,000 302,792,000 323,245,000 242,848,000 316,436,000 720,267,000 6,925,000 202,727,000 239,058,000 272,109,000 15,885,000 218,159,000 
        non-current assets:
      		                              
        property, plant, and equipment
      		5,722,356,000 5,640,435,000 5,531,917,000 5,415,697,000 5,268,063,000 4,858,066,000 4,764,593,000 4,660,104,000 4,556,609,000 4,468,602,000 4,391,993,000 4,320,476,000 4,261,566,000 4,207,328,000 4,129,236,000 4,041,894,000  3,919,096,000 3,849,792,000 3,788,283,000 3,734,039,000 3,680,872,000 3,608,902,000 3,551,065,000  3,416,718,000 3,355,811,000 3,439,460,000  3,370,388,000 
        less: accumulated depreciation
      		1,300,897,000 1,288,422,000 1,284,271,000 1,269,274,000 1,266,222,000 1,245,725,000 1,234,148,000 1,218,580,000 1,198,555,000 1,189,968,000 1,181,230,000 1,164,498,000 1,147,166,000 1,166,150,000 1,150,555,000 1,137,138,000  1,112,734,000 1,093,863,000 1,091,903,000 1,079,269,000 1,073,623,000 1,062,299,000 1,050,850,000  1,027,330,000 1,016,185,000 1,005,117,000  996,994,000 
        total property, plant, and equipment
      		4,421,459,000 4,352,013,000 4,247,646,000 4,146,423,000 4,001,841,000 3,612,341,000 3,530,445,000 3,441,524,000 3,358,054,000 3,278,634,000 3,210,763,000 3,155,978,000 3,114,400,000 3,041,178,000 2,978,681,000 2,904,756,000  2,806,362,000 2,755,929,000 2,696,380,000 2,654,770,000 2,607,249,000 2,546,603,000 2,500,215,000  2,389,388,000 2,339,626,000 2,434,343,000  2,373,394,000 
        other investments
      		69,441,000 80,676,000 81,111,000 82,223,000 82,663,000 82,478,000 83,795,000 84,081,000 102,951,000 104,562,000 104,330,000 93,611,000 95,704,000 96,569,000 96,027,000 96,266,000 42,000 48,006,000 47,725,000 47,434,000 49,259,000 48,963,000 62,130,000 61,928,000 24,000 63,018,000 62,815,000 63,829,000 65,000 65,113,000 
        operating lease right of use asset
      		68,113,000 68,224,000 69,065,000 69,555,000 70,455,000 69,402,000 69,813,000 70,547,000 71,308,000 71,477,000 72,096,000 72,699,000 73,429,000 73,145,000 73,754,000 74,416,000  75,634,000 76,294,000 76,957,000 77,446,000 78,036,000 78,566,000 79,522,000  3,917,000 5,013,000 6,163,000   
        assets under sales-type leases
      		120,450,000 121,470,000 122,517,000 123,588,000 124,623,000 126,712,000 127,794,000 128,840,000 129,882,000 130,952,000 132,045,000 133,159,000 134,302,000 135,480,000 136,673,000 137,837,000  140,189,000 141,408,000 142,586,000 143,759,000 144,971,000 146,208,000 146,937,000  147,918,000 148,886,000    
        goodwill
      		371,257,000 370,815,000 371,040,000 370,889,000 354,534,000 181,393,000 163,166,000 162,966,000 163,344,000 152,399,000 152,670,000 149,836,000 149,283,000 74,732,000 70,714,000 70,570,000  69,789,000 69,313,000 69,330,000 69,225,000 70,292,000 70,183,000 69,220,000  49,333,000 49,393,000 8,954,000  6,563,000 
        other non-current assets
      		146,105,000 146,351,000 150,098,000 151,024,000 160,754,000 139,035,000 112,727,000 111,122,000 106,239,000 100,801,000 96,827,000 97,789,000 91,518,000 88,169,000 75,699,000 74,923,000 613,000 53,419,000 50,516,000 49,767,000 49,129,000 50,945,000 51,446,000 47,729,000 245,000 27,839,000 18,159,000 16,077,000 310,000 12,844,000 
        total non-current assets
      		5,834,847,000 5,564,109,000 5,418,213,000 5,320,447,000 5,166,992,000 4,535,519,000 4,399,246,000 4,311,352,000 4,265,652,000 4,157,678,000 4,078,848,000 4,015,923,000 4,004,113,000 3,818,941,000 3,742,524,000 3,663,269,000 1,081,987,000 3,571,046,000 3,509,659,000 3,455,833,000 3,433,134,000 3,375,249,000 3,324,911,000 3,281,260,000 888,937,000 3,048,891,000 2,999,073,000 2,919,008,000 755,346,000 2,863,248,000 
        total assets
      		6,418,967,000 6,167,041,000 5,853,774,000 5,786,563,000 5,706,892,000 4,944,369,000 4,822,366,000 4,849,066,000 4,867,092,000 4,665,118,000 4,536,705,000 4,592,096,000 4,748,326,000 4,300,712,000 4,100,518,000 4,054,634,000 1,095,780,000 3,929,225,000 3,783,500,000 3,758,625,000 3,756,379,000 3,618,097,000 3,641,347,000 4,001,527,000 895,862,000 3,251,618,000 3,238,131,000 3,191,117,000 771,231,000 3,081,407,000 
        in thousands, except share information
      		2,026,000 2,025,000 2,025,000 2,025,000 2,025,000 2,024,000 2,024,000 2,024,000 2,023,000 2,023,000                     
        liabilities and equity:
      		                              
        current liabilities:
      		                              
        short-term debt
      		171,276,000 171,989,000 195,490,000 157,396,000 81,100,000 159,814,000 79,000,000 94,700,000 89,780,000 71,000,000 41,000,000 72,500,000 258,200,000 141,000,000 222,700,000 332,500,000 144,000,000 399,500,000 240,000,000 236,225,000 304,525,000 223,000,000 233,000,000 550,000,000 24,000,000 65,580,000 20,080,000 176,391,000  100,500,000 
        current maturities of long-term debt
      		160,669,000 160,627,000 115,650,000 141,541,000 36,838,000 20,796,000 866,000 869,000 150,865,000 190,728,000 240,714,000 240,712,000 90,697,000 50,614,000 351,000 339,000  278,000 60,274,000 95,265,000 95,344,000 95,173,000 35,209,000 202,000  94,671,000 104,396,000 104,158,000  84,940,000 
        accounts payable
      		124,844,000 175,566,000 130,508,000 116,819,000 132,814,000 96,260,000 93,564,000 107,888,000 145,361,000 99,326,000 101,369,000 111,152,000 180,667,000 118,274,000 135,364,000 130,557,000 286,000 94,897,000 97,854,000 88,591,000 97,966,000 83,813,000 79,903,000 86,766,000 612,000 76,197,000 76,429,000 103,207,000 168,000 80,143,000 
        taxes accrued
      		17,197,000 18,123,000 20,375,000 11,530,000 24,115,000 17,759,000 11,302,000 27,031,000 15,454,000 17,120,000 12,217,000 31,372,000 15,625,000 18,080,000 11,324,000 14,258,000  16,558,000 15,143,000 23,550,000 13,812,000 13,772,000 18,535,000 23,837,000 127,000 13,382,000 7,003,000 11,004,000  13,074,000 
        interest accrued
      		22,036,000 26,121,000 16,841,000 25,279,000 16,297,000 12,909,000 18,130,000 16,360,000 15,836,000 13,940,000 11,443,000 13,089,000 10,169,000 11,086,000 7,425,000 10,886,000  9,315,000 7,425,000 9,491,000 7,441,000 9,645,000 7,234,000 9,396,000  10,406,000 7,826,000 9,233,000 32,000 9,453,000 
        regulatory liabilities
      		113,914,000 137,974,000 141,356,000 130,944,000 111,050,000 127,640,000 99,663,000 77,659,000 84,962,000 88,376,000 61,546,000 57,523,000 248,582,000 111,551,000 97,277,000 111,791,000  164,168,000 103,210,000 81,314,000 50,362,000 59,236,000 41,126,000 47,137,000  37,573,000 32,484,000 46,770,000  37,504,000 
        operating lease liabilities
      		3,270,000 3,228,000 2,610,000 2,486,000 2,662,000 1,868,000 1,851,000 2,053,000 2,333,000 1,815,000 1,732,000 1,700,000 1,514,000 1,361,000 1,315,000 1,303,000  1,213,000 1,228,000 1,213,000 1,105,000 1,081,000 931,000 1,071,000  3,171,000 4,271,000 4,656,000   
        other current liabilities
      		75,225,000 79,186,000 67,402,000 71,895,000 82,958,000 59,532,000 79,116,000 89,107,000 93,626,000 61,149,000 58,777,000 71,662,000 64,552,000 39,796,000 47,624,000 52,778,000 243,000 39,218,000 43,946,000 48,978,000 52,330,000 49,870,000 54,323,000 62,624,000 37,000 39,873,000 36,612,000 54,543,000  35,497,000 
        total current liabilities
      		730,528,000 836,445,000 742,780,000 683,867,000 513,956,000 567,385,000 435,540,000 468,344,000 696,878,000 590,057,000 570,933,000 644,080,000 898,734,000 511,356,000 539,298,000 658,267,000 160,634,000 734,965,000 572,473,000 585,665,000 627,083,000 551,296,000 486,902,000 798,870,000 28,473,000 358,408,000 307,030,000 526,089,000 9,366,000 382,942,000 
        long-term debt
      		2,272,444,000 2,272,202,000 2,128,101,000 2,086,650,000 2,193,071,000 1,555,000,000 1,574,751,000 1,574,735,000 1,425,435,000 1,424,572,000 1,294,578,000 1,294,590,000 1,246,167,000 1,287,006,000 1,045,530,000 1,044,667,000  916,026,000 915,501,000 860,654,000 860,081,000 860,235,000 918,887,000 953,962,000  806,014,000 806,001,000 632,484,000 -1,000 724,654,000 
        deferred credits and other non-current liabilities:
      		                              
        deferred tax liabilities
      		467,134,000 437,467,000 414,225,000 426,827,000 424,338,000 389,281,000 394,489,000 394,068,000 382,673,000 375,917,000 380,058,000 376,237,000 366,022,000 349,633,000 355,470,000 353,746,000  323,925,000 325,600,000 328,112,000 319,292,000 296,516,000 297,995,000 300,168,000  284,625,000 292,791,000 293,662,000 7,000 274,315,000 
        pension and other postretirement benefit liabilities
      		108,929,000 112,139,000 122,116,000 125,019,000 127,853,000 138,800,000 153,849,000 157,812,000 158,116,000 145,991,000 147,063,000 147,890,000 149,143,000 160,196,000 162,511,000 164,530,000  202,287,000 203,854,000 210,811,000 217,287,000 202,938,000 218,493,000 224,490,000  215,007,000 217,909,000 220,732,000  212,249,000 
        other non-current liabilities
      		408,366,000 186,280,000 183,643,000 183,111,000 175,922,000 135,661,000 122,412,000 120,224,000 119,034,000 127,219,000 128,417,000 117,980,000 123,438,000 110,825,000 111,704,000 112,749,000  115,114,000 117,659,000 118,989,000 120,767,000 123,041,000 120,852,000 119,033,000  123,352,000 129,835,000 120,569,000  140,475,000 
        total deferred credits and other non-current liabilities
      		1,839,094,000 1,583,318,000 1,548,773,000 1,556,808,000 1,543,647,000 1,464,934,000 1,465,359,000 1,462,601,000 1,460,941,000 1,430,949,000 1,430,916,000 1,405,119,000 1,427,984,000 1,381,494,000 1,376,911,000 1,363,756,000  1,386,773,000 1,372,700,000 1,375,982,000 1,380,482,000 1,353,791,000 1,351,557,000 1,346,954,000  1,242,527,000 1,248,354,000 1,238,317,000 7,000 1,236,230,000 
        commitments and contingencies
      		                              
        equity:
      		                              
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 42,080,010, 40,308,777, and 41,563,577 at march 31, 2026 and 2025, and december 31, 2025, respectively
      		1,069,314,000                              
        retained earnings
      		512,213,000 435,823,000 398,553,000 448,517,000 470,795,000 377,685,000 423,718,000 445,058,000 399,911,000 373,231,000 414,398,000 430,597,000 376,473,000 345,570,000 381,963,000 396,769,000  330,109,000 365,501,000 380,939,000 336,523,000 299,150,000 331,648,000 351,050,000 27,025,000 296,256,000 330,018,000 342,734,000 22,137,000 290,059,000 
        accumulated other comprehensive loss
      		-4,626,000 -4,747,000 -6,522,000 -6,682,000 -6,855,000 -7,180,000 -6,500,000 -6,825,000 -7,049,000 -4,979,000 -5,255,000 -6,594,000 -6,285,000 -10,808,000 -11,010,000 -11,207,000  -12,226,000 -12,460,000 -12,681,000 -12,902,000 -10,227,000 -10,413,000 -10,573,000  -8,210,000 -8,324,000 -8,439,000  -7,977,000 
        total equity
      		1,576,901,000 1,475,076,000 1,434,120,000 1,459,238,000 1,456,218,000 1,357,050,000 1,346,716,000 1,343,386,000 1,283,838,000 1,219,540,000 1,240,278,000 1,248,307,000 1,175,441,000 1,120,856,000 1,138,779,000 987,944,000 935,146,000 891,461,000 922,826,000 936,324,000 888,733,000 852,775,000 884,001,000 901,741,000 867,389,000 844,669,000 876,746,000 794,227,000 761,859,000 737,581,000 
        total liabilities and equity
      		6,418,967,000 6,167,041,000 5,853,774,000 5,786,563,000 5,706,892,000 4,944,369,000 4,822,366,000 4,849,066,000 4,867,092,000 4,665,118,000 4,536,705,000 4,592,096,000 4,748,326,000 4,300,712,000 4,100,518,000 4,054,634,000 1,095,780,000 3,929,225,000 3,783,500,000 3,758,625,000 3,756,379,000 3,618,097,000 3,641,347,000 4,001,527,000 895,862,000 3,251,618,000 3,238,131,000 3,191,117,000 771,231,000 3,081,407,000 
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 41,563,577 and 40,222,305 at december 31, 2025 and 2024, respectively
      		 1,044,000,000                             
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 41,506,471, 40,120,524, and 40,222,305 at september 30, 2025 and 2024, and december 31, 2024, respectively
      		  1,042,089,000                            
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 40,909,610, 38,669,098, and 40,222,305 at june 30, 2025 and 2024, and december 31, 2024, respectively
      		   1,017,403,000                           
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 40,308,777, 38,027,266, and 40,222,305 at march 31, 2025 and 2024, and december 31, 2024, respectively
      		    992,278,000                          
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 40,120,524, 36,575,797, and 37,631,212 at september 30, 2024 and 2023, and december 31, 2023, respectively
      		     986,545,000                         
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 38,669,098, 36,064,625, and 37,631,212 at june 30, 2024 and 2023, and december 31, 2023, respectively
      		      929,498,000                        
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 38,027,266, 35,929,228, and 37,631,212 at march 31, 2024 and 2023, and december 31, 2023, respectively
      		       905,153,000                       
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 37,631,212 and 35,524,590 at december 31, 2023 and 2022, respectively
      		        890,976,000                      
        common stock - no par value; authorized 100,000,000 shares; issued and outstanding 36,575,797, 35,098,437, and 35,524,590 at september 30, 2023 and 2022, and december 31, 2022, respectively
      		         851,288,000                     
        in thousands, including share information
      		          2,023,000 2,023,000  2,022,000 2,022,000 2,022,000  2,021,000 2,021,000 2,021,000  2,020,000 2,020,000 2,020,000  2,019,000 2,019,000    
        common stock - no par value; authorized 100,000 shares; issued and outstanding 36,065, 34,754, and 35,525 at june 30, 2023 and 2022, and december 31, 2022, respectively
      		          831,135,000                    
        common stock - no par value; authorized 100,000 shares; issued and outstanding 35,929, 31,380, and 35,525 at march 31, 2023 and 2022, and december 31, 2022, respectively
      		           824,304,000                   
        in thousands
      		            2,022,000        2,020,000       2,019,000  2,018,000 
        common stock - no par value; authorized 100,000 shares; issued and outstanding 35,525 and 31,129 at december 31, 2022 and 2021, respectively
      		            805,253,000                  
        common stock - no par value; authorized 100,000 shares; issued and outstanding 35,098, 30,730, and 31,129 at september 30, 2022 and 2021, and december 31, 2021, respectively
      		             786,094,000                 
        income taxes receivable
      		                  6,000,000 6,000,000 6,000,000    256,000   6,000,000 6,000,000  
        common stock - no par value; authorized 100,000 shares; issued and outstanding 34,754, 30,672, and 31,129 at june 30, 2022 and 2021, and december 31, 2021, respectively
      		              767,826,000                
        common stock - no par value; authorized 100,000 shares; issued and outstanding 31,380, 30,655, and 31,129 at march 31, 2022 and 2021, and december 31, 2021, respectively
      		               602,382,000               
        receivables from affiliates
      		                2,180,000        1,950,000    2,796,000  
        investments in subsidiaries
      		                1,080,949,000        888,477,000    754,971,000  
        deferred tax assets
      		                383,000        191,000      
        payables to affiliates
      		                16,105,000        3,697,000    9,166,000  
        gas reserves
      		                 6,266,000 8,444,000 10,659,000 11,409,000 12,265,000 13,646,000 14,351,000  16,392,000 17,206,000 16,157,000  16,916,000 
        discontinued operations - current assets
      		                              
        discontinued operations - current liabilities
      		                              
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,730, 30,565, and 30,589 at september 30, 2021 and 2020, and december 31, 2020, respectively
      		                 573,578,000             
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,672, 30,546, and 30,589 at june 30, 2021 and 2020, and december 31, 2020, respectively
      		                  569,785,000            
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,655, 30,528, and 30,589 at march 31, 2021 and 2020, and december 31, 2020, respectively
      		                   568,066,000           
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,589 and 30,472 at december 31, 2020 and 2019, respectively
      		                    565,112,000          
        discontinued operations current assets
      		                     16,928,000 16,392,000 15,296,000  14,612,000 14,001,000 14,632,000  12,644,000 
        discontinued operations current liabilities
      		                     13,922,000 13,574,000 12,801,000  13,399,000 13,279,000 13,282,000  13,003,000 
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,565, 30,435, and 30,472 at september 30, 2020 and 2019, and december 31, 2019, respectively
      		                     563,852,000         
        northwest natural holding companyconsolidated balance sheets
      		                              
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,546, 30,422, and 30,472 at june 30, 2020 and 2019, and december 31, 2019, respectively
      		                      562,766,000        
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,528, 28,962, and 30,472 at march 31, 2020 and 2019, and december 31, 2019, respectively
      		                       561,264,000       
        common stock
      		                        840,364,000    739,722,000  
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,435, 28,844, and 28,880 at september 30, 2019 and 2018, and december 31, 2018, respectively
      		                         556,623,000     
        common stock - no par value; authorized 100,000 shares; issued and outstanding 30,422, 28,800, and 28,880 at june 30, 2019 and 2018, and december 31, 2018, respectively
      		                          555,052,000    
        discontinued operations non-current assets
      		                              
        discontinued operations non-current liabilities
      		                              
        common stock - no par value; authorized 100,000 shares; issued and outstanding 28,962, 28,781, and 28,880 at march 31, 2019 and 2018, and december 31, 2018, respectively
      		                           459,932,000   
        northwest natural gas companyconsolidated balance sheets
      		                              
        discontinued operations - non-current liabilities
      		                              
        common stock - no par value; authorized 100,000 shares; issued and outstanding 28,844, 28,713, and 28,736 at september 30, 2018 and 2017, and december 31, 2017, respectively
      		                             455,499,000 
      Cashflow Statements:
      Quarterly
      Annual
        Unit: USD2026-03-31 2025-12-31 2025-09-30 2025-06-30 2025-03-31 2024-09-30 2024-06-30 2024-03-31 2023-12-31 2023-09-30 2023-06-30 2023-03-31 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 
                                     
          operating activities:
        		                             
          net income
        		97,489,000 57,793,000 -29,890,000 -2,500,000 87,916,000 -27,167,000 -2,787,000 63,823,000 44,640,000 -23,687,000 1,244,000 71,671,000 47,936,000 -19,587,000 1,715,000 56,239,000 43,034,000 -20,655,000 -724,000 59,517,000 52,047,000 -17,912,000 -4,852,000 47,498,000 43,979,000 -19,301,000 1,095,000 43,201,000 35,824,000 
          adjustments to reconcile net income to cash from operations:
        		                             
          depreciation
        		44,134,000 42,961,000 40,510,000 41,535,000 40,500,000 34,552,000 33,762,000 33,098,000 32,762,000 30,061,000 31,293,000 31,465,000 31,142,000 29,026,000 28,110,000 28,429,000              
          amortization
        		6,131,000 5,869,000 6,234,000 6,553,000 5,583,000                         
          deferred income taxes
        		24,998,000 18,481,000 -11,062,000 4,057,000 23,997,000 -2,905,000 803,000 8,041,000 2,288,000 -1,932,000 3,382,000 5,228,000 9,651,000 -2,900,000 1,879,000 8,780,000 10,475,000 1,700,000 -2,097,000 3,145,000 19,057,000 1,614,000 1,418,000 -3,422,000 1,575,000 -3,446,000 -389,000 6,306,000 10,402,000 
          qualified defined benefit pension plan expense
        		2,307,000 2,589,000 2,331,000 2,718,000 2,719,000 883,000 1,082,000 1,082,000  -694,000 -338,000 -791,000 1,338,000 1,131,000 1,441,000 1,441,000 4,481,000 4,201,000 3,937,000 3,937,000 4,570,000 4,908,000 4,446,000 4,446,000 6,033,000 3,476,000 3,489,000 3,499,000 3,658,000 
          contributions to qualified defined benefit pension plans
        		-2,900,000 -2,900,000 -2,900,000 -2,900,000 -2,610,000 -14,460,000           0 0 -5,050,000 -4,540,000 -5,310,000 -15,200,000 -5,310,000 -3,160,000 -3,160,000 -3,160,000 -3,160,000 -1,490,000 -3,850,000 
          deferred environmental expenditures
        		-6,079,000 -7,819,000 -6,158,000 -4,729,000 -6,991,000 -4,647,000 -7,864,000 -6,264,000 -11,165,000 -5,155,000 -5,619,000 -4,113,000 -3,723,000 -4,829,000 -5,263,000 -4,345,000 -3,235,000 -5,327,000 -5,355,000 -4,270,000 -11,402,000 -6,572,000 -5,916,000 -3,981,000 -5,234,000 -3,844,000 -3,463,000 -3,685,000 -3,981,000 
          environmental remediation expense
        		6,325,000 4,827,000 1,247,000 2,296,000 6,253,000 1,151,000 2,329,000 5,746,000 4,352,000 1,032,000 2,140,000 5,375,000 4,439,000 980,000 2,267,000 4,703,000              
          asset optimization revenue sharing bill credits
        		-23,156,000 0 0 0 -15,549,000 0 -8,590,000 -20,608,000 0 0 0 -10,471,000 0 0 0 -41,102,000              
          other
        		4,207,000 4,685,000 191,000 4,778,000 3,016,000 -7,398,000 6,793,000 8,905,000 4,893,000 4,011,000 5,559,000 8,509,000 4,918,000 6,679,000 3,636,000 6,325,000 3,649,000 4,205,000 4,529,000 -2,919,000 -2,459,000 1,448,000 -12,430,000 6,499,000 3,259,000 2,776,000 3,111,000 3,171,000 55,000 
          changes in assets and liabilities:
        		                             
          receivables
        		21,656,000 -121,164,000 7,783,000 106,042,000 15,509,000 12,114,000 100,723,000 17,839,000 -131,320,000 18,332,000 125,238,000 38,727,000 -191,209,000 18,302,000 57,789,000 38,664,000 -126,856,000 10,693,000 72,089,000 1,044,000 -94,035,000 3,282,000 69,109,000 4,845,000 -70,941,000 11,169,000 73,927,000 -4,891,000 -83,013,000 
          inventories
        		-7,598,000 -19,632,000 -5,181,000 -22,661,000 18,279,000 -1,319,000 -7,659,000 13,070,000 -17,621,000 -26,568,000 -26,045,000 46,129,000 12,194,000 -32,742,000 -32,606,000 23,885,000 2,880,000 -20,973,000 -12,788,000 16,454,000 2,388,000 -1,074,000 -9,623,000 9,571,000 -2,697,000 -18,222,000 -6,179,000 21,108,000 8,341,000 
          income and other taxes
        		13,408,000 -21,564,000 7,186,000 -9,579,000 18,084,000 -5,031,000 -6,959,000 21,796,000 -10,016,000 -6,064,000 -10,733,000 25,567,000 -12,539,000 2,206,000 2,805,000 14,436,000 -30,025,000 -1,847,000 -1,508,000 22,975,000 -22,748,000 -8,928,000 -945,000 21,911,000 -21,014,000 5,210,000 8,894,000 7,406,000  
          accounts payable
        		-31,219,000 14,760,000 -16,227,000 7,395,000 4,187,000 -535,000 19,964,000 -30,930,000 -263,000 9,240,000 -1,162,000 -47,773,000 54,518,000 -16,282,000 2,759,000 -16,487,000 26,785,000 -818,000 -14,910,000 -2,329,000 4,401,000 -1,392,000 4,511,000 -23,430,000 13,219,000 -3,924,000 -12,960,000 -14,883,000 39,721,000 
          deferred gas costs
        		-29,651,000 19,040,000 -7,994,000 -28,288,000 -16,959,000 6,715,000 -5,610,000 -8,808,000 61,049,000 7,692,000 -5,070,000 -11,300,000 14,119,000 -4,392,000 -9,121,000 11,728,000 -7,162,000 -6,417,000 1,950,000 -28,912,000 20,062,000 -2,587,000 -8,124,000 8,239,000 23,614,000 -2,235,000 -25,668,000 -19,182,000 -16,767,000 
          asset optimization revenue sharing
        		4,297,000 4,833,000 9,413,000 5,740,000 4,357,000 6,459,000 4,392,000 -108,000 3,970,000 6,611,000 4,287,000 7,769,000 11,308,000 13,700,000 4,575,000 -646,000 3,051,000 4,535,000 2,239,000 34,633,000          
          decoupling mechanism
        		-15,803,000 -5,855,000 -6,291,000 -13,371,000 -1,422,000 -2,096,000 -2,342,000 6,427,000 913,000 -2,774,000 -8,251,000 -1,303,000 3,798,000 -2,545,000 5,235,000 4,434,000 3,966,000 -2,312,000 -7,516,000 656,000 -1,291,000 -106,000 -1,856,000 6,137,000 7,566,000 2,460,000 732,000 7,903,000  
          cloud-based software
        		-2,490,000 -2,419,000 -4,143,000 -1,624,000 -2,195,000 -3,883,000 -9,939,000 -6,485,000 -3,991,000 -5,087,000 -3,556,000 -3,673,000 -6,576,000                 
          regulatory accounts
        		13,208,000 -227,000 5,190,000 -543,000 2,155,000 2,446,000 1,531,000 13,335,000                      
          cash from operating activities
        		116,127,000 3,272,000 -15,918,000 102,160,000 179,610,000 -26,379,000 121,037,000 125,039,000 -21,554,000 3,649,000 120,993,000 176,861,000 -18,289,000 -30,603,000 55,527,000 141,037,000 -40,230,000 -12,557,000 57,216,000 137,065,000 -5,520,000 -11,006,000 56,683,000 102,863,000 30,885,000 182,000 50,315,000 104,794,000 10,242,000 
          investing activities:
        		                             
          capital expenditures
        		-113,656,000 -134,241,000 -109,988,000 -120,480,000 -102,184,000 -95,332,000 -116,712,000 -82,217,000 -84,600,000 -97,884,000 -73,598,000 -71,265,000 -86,760,000 -84,146,000 -99,182,000 -68,514,000 -65,861,000 -82,268,000 -64,406,000 -65,702,000 -79,680,000 -71,054,000 -64,836,000 -57,446,000 -68,387,000 -61,846,000 -42,383,000 -48,764,000 -55,841,000 
          free cash flows
        		2,471,000 -130,969,000 -125,906,000 -18,320,000 77,426,000 -121,711,000 4,325,000 42,822,000 -106,154,000 -94,235,000 47,395,000 105,596,000 -105,049,000 -114,749,000 -43,655,000 72,523,000 -106,091,000 -94,825,000 -7,190,000 71,363,000 -85,200,000 -82,060,000 -8,153,000 45,417,000 -37,502,000 -61,664,000 7,932,000 56,030,000 -45,599,000 
          acquisitions, net of cash acquired
        		 -6,803,000 1,000 -60,837,000 -270,492,000    -4,285,000 1,000 -2,781,000 -468,000 -91,927,000     -320,000 -13,000 -42,000 -185,000 -138,000 -57,000 -37,883,000  -378,000    
          purchase of equity method investment
        		-1,000,000 0 0 0 -1,000,000 0 0 -1,000,000                      
          cash used by investing activities
        		-116,053,000                             
          financing activities:
        		                             
          proceeds from common stock issued
        		22,264,000 -151,000 23,185,000 23,423,000 961,000 55,577,000 22,768,000 12,218,000 25,540,000 18,883,000 5,403,000 16,669,000 17,632,000 16,876,000 164,115,000 9,938,000          0    
          long-term debt issued
        		 200,000,000 185,000,000 0 375,000,000 0 0 150,000,000 0 130,000,000 0 200,000,000 0 289,308,000   75,000,000 0   0 0 0 150,000,000 -35,000,000 0   0 
          long-term debt retired
        		-121,000 -10,168,000 -169,937,000 -1,511,000 -1,511,000 0 0 -150,000,000 -40,000,000        35,000,000 -60,000,000   0 0 0 -75,000,000 -20,000,000    -75,000,000 
          changes in other short-term debt
        		-713,000 -23,501,000 38,072,000 76,318,000 -94,010,000 80,814,000 -15,700,000 4,920,000 18,660,000 30,000,000 -31,500,000 -185,700,000 117,200,000 -81,700,000 -109,800,000 -57,000,000              
          cash dividend payments on common stock
        		-19,775,000 -19,723,000 -19,406,000 -19,076,000 -19,104,000 -18,181,000 -17,854,000 -17,746,000 -17,226,000 -16,821,000 -16,761,000 -16,532,000 -16,337,000 -16,123,000 -15,859,000 -14,452,000 -14,229,000 -13,985,000 -13,984,000 -13,858,000 -13,912,000 -13,829,000 -13,845,000 -13,834,000 -13,767,000 -13,689,000 -12,981,000 -12,935,000 -12,924,000 
          payment of financing fees
        		-54,000 -3,117,000 -1,690,000 -78,000 -4,307,000 -153,000 0 -748,000                      
          shares withheld for tax purposes
        		-1,988,000 -8,000 -54,000 -1,000 -1,536,000 -5,000 0 -1,314,000                      
          cash from financing activities
        		-779,000 143,397,000    118,002,000 -11,303,000 -2,917,000 -15,325,000 111,728,000 -43,382,000 11,187,000 117,439,000 208,155,000 38,802,000 -62,764,000 125,313,000 87,557,000 9,590,000 -83,132,000 67,274,000 -23,779,000 -331,715,000 459,997,000 -13,015,000 21,348,000 100,094,000 -53,554,000 28,804,000 
          increase in cash, cash equivalents and restricted cash
        		-705,000   -321,000 59,003,000 -34,231,000 -8,219,000 39,634,000 -121,856,000 16,397,000 -911,000 115,030,000 -79,306,000 90,235,000 -5,608,000 8,523,000 12,875,000 -638,000 2,798,000 -9,942,000          
          cash, cash equivalents and restricted cash, beginning of period
        		41,077,000 0 0 0 47,982,000 0 0 49,624,000 0 0 0 40,964,000 0 0 0 27,120,000 -19,715,000 0 0 35,454,000          
          cash, cash equivalents and restricted cash, end of period
        		40,372,000 5,247,000 -70,834,000 -321,000 106,985,000 -34,231,000 -8,219,000 89,258,000 -121,856,000 16,397,000 -911,000 155,994,000 -79,306,000 90,235,000 -5,608,000 35,643,000 -6,840,000 -638,000 2,798,000 25,512,000          
          supplemental disclosure of cash flow information:
        		                             
          interest paid, net of capitalization
        		36,443,000 20,757,000 37,943,000 22,448,000 30,109,000 23,035,000 16,758,000 18,044,000 28,227,000 15,594,000 21,472,000 14,904,000 19,049,000 8,907,000 14,890,000 7,977,000 11,485,000 8,939,000 12,995,000 8,976,000 12,822,000 6,673,000 14,788,000 8,368,000 12,191,000 8,011,000 11,749,000 7,976,000 12,503,000 
          income taxes paid, net of refunds
        		1,400,000 2,301,000 1,030,000 7,329,000 750,000 5,580,000 9,251,000 1,000,000 5,300,000 6,800,000 10,863,000 1,300,000 673,000 1,020,000 313,000 773,000  -425,000            
          regulatory disallowance of line extension allowances
        		                             
          rng facility prepayment
        		                             
          cash from investing activities
        		 -141,422,000 -111,593,000 -180,912,000 -374,975,000 -125,854,000 -117,953,000 -82,488,000 -84,977,000 -98,980,000 -78,522,000 -73,018,000 -178,456,000 -87,317,000 -99,937,000 -69,750,000 -72,208,000 -75,638,000 -64,008,000 -63,875,000 -67,512,000 -66,346,000 -58,990,000 -101,429,000 -17,787,000 -71,893,000 -102,341,000 -51,056,000 -56,378,000 
          income taxes paid, net of refunds:
        		                             
          u.s. federal taxes
        		                             
          state and local taxes
        		                             
          oregon
        		                             
          other states
        		                             
          non-cash activities:
        		                             
          shares issued in connection with business combinations
        		                             
          debt assumed in connection with business combinations
        		                             
          decrease in cash, cash equivalents and restricted cash
        		                             
          cash provided (used) by financing activities
        		   78,431,000 254,368,000                         
          regulatory amortization of gas reserves
        		      539,000 546,000 685,000 854,000 845,000 833,000 1,062,000 1,543,000 1,503,000 1,481,000 2,291,000 4,009,000 3,963,000 3,634,000 4,068,000 5,144,000 4,480,000 4,087,000 4,698,000 5,007,000 4,687,000 4,780,000 4,628,000 
          qualified defined benefit pension plan (benefit) expense
        		                             
          proceeds from sale of equity method investment
        		                    0         
          proceeds from term loan due within one year
        		                0 0   0 0 0 150,000,000      
          repayment of term loan
        		                             
          repayments of commercial paper, maturities greater than three months
        		                             
          gain on sale of discontinued operations, net of tax
        		                             
          discontinued operations
        		                    1,188,000 1,253,000 -171,000 -376,000  -893,000 1,377,000 -739,000 -1,861,000 
          leasehold improvement expenditures
        		                -794,000 -407,000 -109,000 -54,000 -51,000 -308,000 -1,194,000 -6,325,000      
          proceeds from the sale of assets
        		            331,000 194,000 150,000 195,000 1,214,000 478,000 274,000 1,960,000 146,000 98,000        
          proceeds from sale of discontinued operations
        		                             
          proceeds from commercial paper, maturities greater than three months
        		                             
          repayment of commercial paper, maturities greater than three months
        		                             
          depreciation and amortization
        		                25,825,000 28,438,000 28,144,000 28,097,000 27,238,000 25,934,000 25,836,000 24,675,000 23,071,000 23,375,000 22,387,000 21,572,000 21,649,000 
          regulatory disallowance of pension costs
        		                        0 0 0 10,500,000  
          cash contributions received from parent
        		                             
          income taxes paid
        		                             
          amortization of environmental remediation
        		                 806,000 1,509,000 3,777,000  867,000 1,622,000 4,005,000  967,000 -2,656,000 8,947,000 3,599,000 
          change in other short-term debt
        		                 159,500,000 -1,200,000 31,700,000          
          repayments of commercial paper, maturities greater than 90 days
        		                  -95,025,000 -100,000,000          
          income taxes paid (refunded)
        		                   800,000  8,800,000 800,000 -256,000  -1,000 -6,005,000 -90,000  
          regulatory revenue deferral from the tcja
        		                            946,000 
          proceeds from stock options exercised
        		                    0   68,000  0 177,000 1,546,000 178,000 
          proceeds from issuances of commercial paper, maturities greater than 90 days
        		                             
          stock purchases related to acquisitions
        		                            0 
          increase in cash and cash equivalents
        		                    -5,758,000 -101,131,000 -334,022,000 461,431,000 83,000 -50,363,000 48,068,000 184,000 -17,332,000 
          cash and cash equivalents, beginning of period
        		                    0 0 0 9,648,000 -4,686,000 0 0 12,633,000 0 
          cash and cash equivalents, end of period
        		                    -5,758,000 -101,131,000 -334,022,000 471,079,000 -4,603,000 -50,363,000 48,068,000 12,817,000 -17,332,000 
          regulatory revenue recovery deferral from the tcja
        		                         103,000 189,000 450,000  
          interest accrued
        		                     2,411,000 -2,162,000 1,945,000 -2,932,000 2,580,000 -1,407,000 1,927,000 -2,154,000 
          change in short-term debt
        		                     -10,000,000 -317,000,000 250,900,000 59,640,000 45,500,000 -156,311,000 -41,229,000 116,974,000 
          repurchases related to stock-based compensation
        		                             
          regulatory disallowance of prior environmental cost deferrals
        		                             
          income taxes