v3.26.1
Revenue - Disaggregation of Revenue (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Disaggregation of Revenue [Line Items]        
Electric $ 1,015,155 $ 832,355 $ 2,275,734 $ 1,859,303
Natural gas 287,903 270,370 867,053 835,297
Other 9,746 17,740 18,274 27,868
Other 9,746 17,740 18,274 27,868
Revenues 1,312,804 1,120,465 3,161,061 2,722,468
Puget LNG        
Disaggregation of Revenue [Line Items]        
Natural gas     1,500 2,000
Other 9,689 10,406 18,099 20,435
Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,298,748 1,093,823 3,194,360 2,741,696
Total other revenue2 5,168 17,149 (49,926) (37,704)
Electric 1,015,155 832,355 2,275,734 1,859,303
Natural gas 288,704 271,283 868,525 837,256
Other 57 7,334 175 7,433
Other 57 7,334 175 7,433
Revenues 1,303,916 1,110,972 3,144,434 2,703,992
Consolidation, Elimination, Obligor Group and Nonobligor Subsidiary        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers (801) (913) (1,472) (1,959)
Electricity, US Regulated [Member] | Puget LNG        
Disaggregation of Revenue [Line Items]        
Other 0 0 0 0
Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 1,008,285 812,803 2,303,579 1,867,183
Total other revenue2 6,870 19,552 (27,845) (7,880)
Deferred Emission Compliance Auction Proceeds, Passback to Customers 55,300   126,600  
Electricity, US Regulated [Member] | Consolidation, Elimination, Obligor Group and Nonobligor Subsidiary        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Natural Gas, US Regulated [Member] | Puget LNG        
Disaggregation of Revenue [Line Items]        
Other 0 0 0 0
Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 290,406 273,686 890,606 867,080
Total other revenue2 (1,702) (2,403) (22,081) (29,824)
Deferred Emission Compliance Auction Proceeds, Passback to Customers 21,000 15,700 67,900 53,600
Natural Gas, US Regulated [Member] | Consolidation, Elimination, Obligor Group and Nonobligor Subsidiary        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers (801) (913) (1,472) (1,959)
Other Revenue From Contracts with Customers [Member] | Puget LNG        
Disaggregation of Revenue [Line Items]        
Other 9,689 10,406 18,099 20,435
Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 57 7,334 175 7,433
Total other revenue2 0 0 0 0
Other Revenue From Contracts with Customers [Member] | Consolidation, Elimination, Obligor Group and Nonobligor Subsidiary        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Residential | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 666,214 561,412 1,747,368 1,518,540
Residential | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 499,231 398,937 1,206,587 982,700
Residential | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 166,983 162,475 540,781 535,840
Residential | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Commercial | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 467,958 378,478 1,054,857 879,267
Commercial | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 377,823 294,602 804,765 635,910
Commercial | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 90,135 83,876 250,092 243,357
Commercial | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Industrial | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 50,016 39,085 106,342 86,096
Industrial | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 44,578 33,655 90,624 70,344
Industrial | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 5,438 5,430 15,718 15,752
Industrial | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Other | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 7,262 5,032 14,179 11,274
Other | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 7,262 5,032 14,179 11,274
Other | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Other | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Wholesale | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 9,188 63,080 28,499 135,072
Wholesale | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 9,188 63,080 28,499 135,072
Wholesale | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Wholesale | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Transmission and transportation | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 22,046 14,840 48,583 32,938
Transmission and transportation | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 12,219 8,717 26,783 17,481
Transmission and transportation | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 9,827 6,123 21,800 15,457
Transmission and transportation | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 0 0 0 0
Miscellaneous1 | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 76,064 31,896 194,532 78,509
Miscellaneous1 | Electricity, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 57,984 8,780 132,142 14,402
Miscellaneous1 | Natural Gas, US Regulated [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers 18,023 15,782 62,215 56,674
Miscellaneous1 | Other Revenue From Contracts with Customers [Member] | Subsidiaries        
Disaggregation of Revenue [Line Items]        
Total revenue from contracts with customers $ 57 $ 7,334 $ 175 $ 7,433