Puget Sound Energy 10-K 20 Feb 25 2024 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2024	Jun. 30, 2024
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	1-16305
Entity Registrant Name	PUGET ENERGY INC /WA
Entity Incorporation, State or Country Code	WA
Entity Address, Address Line One	355 110th Ave NE
Entity Address, City or Town	Bellevue
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98004
City Area Code	(425)
Local Phone Number	454-6363
Entity Tax Identification Number	91-1969407
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Central Index Key	0001085392
Entity Public Float		$ 0
Entity Common Stock, Shares Outstanding	200
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false
Document Financial Statement Error Correction [Flag]	false
Subsidiaries [Member]
Document Information [Line Items]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2024
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	1-4393
Entity Registrant Name	PUGET SOUND ENERGY, INC.
Entity Incorporation, State or Country Code	WA
Entity Address, Address Line One	355 110th Ave NE
Entity Address, City or Town	Bellevue
Entity Address, State or Province	WA
Entity Address, Postal Zip Code	98004
City Area Code	(425)
Local Phone Number	454-6363
Entity Tax Identification Number	91-0374630
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Central Index Key	0000081100
Entity Public Float		$ 0
Entity Common Stock, Shares Outstanding	85,903,791
Document Fiscal Year Focus	2024
Document Fiscal Period Focus	FY
Amendment Flag	false
Document Financial Statement Error Correction [Flag]	false

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2024
Auditor [Line Items]
Auditor Location	Seattle, Washington
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	238
Subsidiaries [Member]
Auditor [Line Items]
Auditor Location	Seattle, Washington
Auditor Name	PricewaterhouseCoopers LLP
Auditor Firm ID	238

CONSOLIDATED STATEMENTS OF INCO

CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Electric	$ 3,332,695	$ 3,345,867	$ 2,961,457
Natural gas	1,488,570	1,423,276	1,209,636
Other	34,950	47,431	50,069
Total operating revenue	4,856,215	4,816,574	4,221,162
Purchased electricity	1,196,897	1,110,572	1,038,728
Electric generation fuel	336,725	457,287	348,159
Residential exchange	(85,175)	(77,223)	(77,715)
Purchased natural gas	679,433	641,371	500,849
Unrealized (gain) loss on derivative instruments, net	(33,911)	284,495	(261,177)
Utility operations and maintenance	785,088	735,278	665,259
Non-utility expense and other	46,056	56,515	59,804
Depreciation and amortization	787,986	751,335	663,232
Conservation amortization	137,147	121,340	116,942
Taxes other than income taxes	398,773	404,538	389,442
Total operating expenses	4,249,019	4,485,508	3,443,523
Operating income (loss)	607,196	331,066	777,639
Other income	102,882	66,829	45,450
Other expense	(19,566)	(14,765)	(19,569)
AFUDC	37,660	24,687	18,444
Interest expense	(432,194)	(381,511)	(347,921)
Income (loss) before income taxes	295,978	26,306	474,043
Income tax (benefit) expense	30,723	(27,434)	59,698
Net income (loss)	265,255	53,740	414,345
Subsidiaries [Member]
Electric	3,332,695	3,345,867	2,961,457
Natural gas	1,492,254	1,424,368	1,209,636
Other	282	16,383	45,080
Total operating revenue	4,825,231	4,786,618	4,216,173
Purchased electricity	1,196,897	1,110,572	1,038,728
Electric generation fuel	336,725	457,287	348,159
Residential exchange	(85,175)	(77,223)	(77,715)
Purchased natural gas	679,433	641,371	500,849
Unrealized (gain) loss on derivative instruments, net	(33,911)	284,495	(261,177)
Utility operations and maintenance	785,088	735,278	665,259
Non-utility expense and other	21,664	28,658	47,194
Depreciation and amortization	781,325	744,629	657,349
Conservation amortization	137,147	121,340	116,942
Taxes other than income taxes	403,918	404,759	388,123
Total operating expenses	4,223,111	4,451,166	3,423,711
Operating income (loss)	602,120	335,452	792,462
Other income	100,071	64,230	36,684
Other expense	(19,566)	(14,765)	(19,569)
AFUDC	37,660	24,687	18,444
Interest expense	(321,550)	(285,148)	(256,774)
Income (loss) before income taxes	398,735	124,456	571,247
Income tax (benefit) expense	52,587	(6,603)	80,295
Net income (loss)	$ 346,148	$ 131,059	$ 490,952

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net Income (Loss)	$ 265,255	$ 53,740	$ 414,345
Other comprehensive income (loss):
Net unrealized gain (loss) from pension and postretirement plans, net of tax	25,629	42,313	2,658
Other comprehensive income (loss)	25,629	42,313	2,658
Comprehensive income (loss)	290,884	96,053	417,003
Subsidiaries [Member]
Net Income (Loss)	346,148	131,059	490,952
Other comprehensive income (loss):
Net unrealized gain (loss) from pension and postretirement plans, net of tax	27,761	44,265	9,711
Amortization of treasury interest rate swaps to earnings, net of tax	386	385	386
Other comprehensive income (loss)	28,147	44,650	10,097
Comprehensive income (loss)	$ 374,295	$ 175,709	$ 501,049

CONSOLIDATED STATEMENTS OF CO_2

CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Net unrealized gain (loss) from pension and postretirement plans, tax	$ 9,144	$ 8,916	$ 708
Subsidiaries [Member]
Net unrealized gain (loss) from pension and postretirement plans, tax	9,710	9,434	2,580
Amortization of Financing Cash Flow Hedge Contracts to Earnings Tax	$ 101	$ 103	$ 102

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Utility Plant [Abstract]
Electric plant	$ 12,476,380	$ 11,304,995
Natural gas plant	5,178,523	4,928,725
Common plant	1,089,618	1,003,519
Less: Accumulated depreciation and amortization	(5,101,926)	(4,643,833)
Net utility plant	13,642,595	12,593,406
Other property and investments:
Goodwill	1,656,513	1,656,513
Other property and investments	307,813	312,353
Total other property and investments	1,964,326	1,968,866
Current assets:
Cash and cash equivalents	101,836	148,548
Restricted cash	38,865	66,027
Accounts receivable, net of allowance for doubtful accounts of $40,436 and $38,211, respectively	538,930	546,701
Unbilled revenue	273,420	243,342
Materials and supplies, at average cost	201,847	173,445
Fuel and natural gas inventory, at average cost	88,964	87,510
Unrealized gain on derivative instruments	32,591	74,225
GHG emission allowances	43,592	937
Prepaid expenses and other	83,851	75,342
Power contract acquisition adjustment gain	4,122	16,358
Total current assets	1,408,018	1,432,435
Other long-term and regulatory assets:
Power cost adjustment mechanism	61,202	48,427
Regulatory assets related to power contracts	4,779	6,266
Other regulatory assets	1,355,291	1,163,551
Unrealized gain on derivative instruments	6,245	35,324
Power contract acquisition adjustment gain	26,444	30,566
Operating lease right-of-use asset	181,397	194,321
Other	310,094	259,291
Total other long-term and regulatory assets	1,945,452	1,737,746
Total assets	18,960,391	17,732,453
Common shareholder’s equity:
Common stock $0.01 par value, 1,000 shares authorized, 200 shares outstanding	0	0
Additional paid-in capital	3,816,332	3,523,532
Retained earnings	1,508,705	1,419,311
Accumulated other comprehensive income (loss), net of tax	43,168	17,539
Total common shareholder’s equity	5,368,205	4,960,382
Long-term debt:
First mortgage bonds and senior notes	5,845,000	5,062,000
Pollution control bonds	161,860	161,860
Long-term debt	1,600,000	2,000,000
Debt discount, issuance costs and other	182,941	187,218
Total long-term debt	7,423,919	7,036,642
Total capitalization	12,792,124	11,997,024
Current liabilities:
Accounts payable	549,710	455,942
Short-term debt	378,400	598,100
Current maturities of long-term debt	417,000	0
Accrued expenses:
Taxes	105,080	102,627
Salaries and wages	74,294	68,726
Interest	66,113	63,829
Unrealized loss on derivative instruments	218,443	185,788
Power contract acquisition adjustment loss	1,074	1,487
Operating lease liabilities	22,761	21,629
Compliance obligation	43,592	937
Other	105,605	67,653
Total current liabilities	1,982,072	1,566,718
Other Long-term and regulatory liabilities:
Deferred income taxes	997,680	950,229
Unrealized loss on derivative instruments	171,488	38,049
Purchased gas adjustment liability	58,657	132,082
Regulatory liabilities	1,075,620	1,022,457
Regulatory liability for deferred income taxes	721,907	760,961
Regulatory liabilities related to power contracts	30,566	46,924
Power contract acquisition adjustment loss	3,705	4,779
Operating lease liabilities	166,700	180,754
Finance lease liabilities	96,850	99,512
Compliance obligation	73,049	168,879
Other deferred credits	789,973	764,085
Total long-term and regulatory liabilities	4,186,195	4,168,711
Commitments and contingencies (Note 16)
Total capitalization and liabilities	$ 18,960,391	$ 17,732,453
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000	1,000
Common stock, shares outstanding (in shares)	200	200
Subsidiaries [Member]
Utility Plant [Abstract]
Electric plant	$ 14,188,252	$ 13,043,559
Natural gas plant	5,726,641	5,480,496
Common plant	1,110,364	1,024,319
Less: Accumulated depreciation and amortization	(7,382,662)	(6,954,968)
Net utility plant	13,642,595	12,593,406
Other property and investments:
Other property and investments	71,005	69,808
Total other property and investments	71,005	69,808
Current assets:
Cash and cash equivalents	100,105	144,825
Restricted cash	38,865	66,027
Accounts receivable, net of allowance for doubtful accounts of $40,436 and $38,211, respectively	539,072	546,463
Unbilled revenue	273,420	243,342
Materials and supplies, at average cost	201,847	173,445
Fuel and natural gas inventory, at average cost	87,118	85,726
Unrealized gain on derivative instruments	32,591	74,225
GHG emission allowances	43,592	937
Prepaid expenses and other	83,835	75,323
Total current assets	1,400,445	1,410,313
Other long-term and regulatory assets:
Power cost adjustment mechanism	61,202	48,427
Other regulatory assets	1,355,291	1,163,551
Unrealized gain on derivative instruments	6,245	35,324
Operating lease right-of-use asset	181,397	194,321
Other	308,204	256,617
Total other long-term and regulatory assets	1,912,339	1,698,240
Total assets	17,026,384	15,771,767
Common shareholder’s equity:
Common stock $0.01 par value, 1,000 shares authorized, 200 shares outstanding	859	859
Additional paid-in capital	3,927,905	3,635,105
Retained earnings	1,665,370	1,473,218
Accumulated other comprehensive income (loss), net of tax	(30,247)	(58,394)
Total common shareholder’s equity	5,563,887	5,050,788
Long-term debt:
First mortgage bonds and senior notes	5,845,000	5,062,000
Pollution control bonds	161,860	161,860
Debt discount, issuance costs and other	45,835	39,813
Total long-term debt	5,961,025	5,184,047
Total capitalization	11,524,912	10,234,835
Current liabilities:
Accounts payable	550,765	457,965
Short-term debt	40,000	336,600
Current maturities of long-term debt	17,000	0
Accrued expenses:
Taxes	105,754	102,775
Salaries and wages	74,294	68,726
Interest	56,215	53,834
Unrealized loss on derivative instruments	218,443	185,788
Operating lease liabilities	22,761	21,629
Compliance obligation	43,592	937
Other	105,605	67,653
Total current liabilities	1,234,429	1,295,907
Other Long-term and regulatory liabilities:
Deferred income taxes	1,117,492	1,078,847
Unrealized loss on derivative instruments	171,488	38,049
Purchased gas adjustment liability	58,657	132,082
Regulatory liabilities	1,074,427	1,021,193
Regulatory liability for deferred income taxes	722,558	761,621
Operating lease liabilities	166,700	180,754
Finance lease liabilities	96,850	99,512
Compliance obligation	73,049	168,879
Other deferred credits	785,822	760,088
Total long-term and regulatory liabilities	4,267,043	4,241,025
Commitments and contingencies (Note 16)
Total capitalization and liabilities	$ 17,026,384	$ 15,771,767
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares outstanding (in shares)	85,903,791	85,903,791

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Assets
Construction work in progress	$ 1,577,695	$ 1,156,265
Current assets:
Allowance for doubtful accounts	$ 40,436	$ 38,211
Common shareholder’s equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,000	1,000
Common stock, shares outstanding (in shares)	200	200
Subsidiaries [Member]
Assets
Construction work in progress	$ 1,577,695	$ 1,156,265
Current assets:
Allowance for doubtful accounts	$ 40,436	$ 38,211
Common shareholder’s equity:
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares outstanding (in shares)	85,903,791	85,903,791

CONSOLIDATED STATEMENTS OF COMM

CONSOLIDATED STATEMENTS OF COMMON SHAREHOLDER'S EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Subsidiaries [Member]	Subsidiaries [Member] Common Stock	Subsidiaries [Member] Additional Paid-in Capital	Subsidiaries [Member] Retained Earnings	Subsidiaries [Member] Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2021	$ 4,563,316		$ 3,523,532	$ 1,067,216	$ (27,432)	$ 4,355,430	$ 859	$ 3,485,105	$ 982,607	$ (113,141)
Balance (in shares) at Dec. 31, 2021		200					85,903,791
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	414,345			414,345		490,952			490,952
Dividends, Common Stock	(16,230)			(16,230)		(35,396)			(35,396)
Other comprehensive income (loss)	2,658				2,658	10,097				10,097
Capital contribution	0					50,000		50,000
Balance at Dec. 31, 2022	4,964,089		3,523,532	1,465,331	(24,774)	4,871,083	$ 859	3,535,105	1,438,163	(103,044)
Balance (in shares) at Dec. 31, 2022		200					85,903,791
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	53,740			53,740		131,059			131,059
Dividends, Common Stock	(99,760)			(99,760)		(96,004)			(96,004)
Other comprehensive income (loss)	42,313				42,313	44,650				44,650
Capital contribution	0					100,000		100,000
Balance at Dec. 31, 2023	$ 4,960,382		3,523,532	1,419,311	17,539	$ 5,050,788	$ 859	3,635,105	1,473,218	(58,394)
Balance (in shares) at Dec. 31, 2023	200	200				85,903,791	85,903,791
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	$ 265,255			265,255		$ 346,148			346,148
Dividends, Common Stock	(175,861)			(175,861)		(153,996)			(153,996)
Other comprehensive income (loss)	25,629				25,629	28,147				28,147
Capital contribution	292,800		292,800			292,800		292,800
Balance at Dec. 31, 2024	$ 5,368,205		$ 3,816,332	$ 1,508,705	$ 43,168	$ 5,563,887	$ 859	$ 3,927,905	$ 1,665,370	$ (30,247)
Balance (in shares) at Dec. 31, 2024	200	200				85,903,791	85,903,791

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating Activities:
Net Income (Loss)	$ 265,255	$ 53,740	$ 414,345
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	787,986	751,335	663,232
Conservation amortization	137,147	121,340	116,942
Deferred income taxes and tax credits, net	(747)	(94,835)	17,941
Net unrealized (gain) loss on derivative instruments	(33,911)	284,495	(261,177)
AFUDC - equity	(59,466)	(39,012)	(28,310)
Other non-cash	22,476	9,966	4,757
Funding of pension liability	(18,000)	(18,000)	(18,000)
Regulatory assets and liabilities	(89,838)	153,069	(90,335)
Purchased gas adjustment	(73,426)	152,763	37,256
GHG emission allowances	(154,728)	(129,195)	0
Other long term assets and liabilities	(3,674)	(16,714)	(23,639)
Change in certain current assets and liabilities:
Accounts receivable and unbilled revenue	(22,307)	138,646	(258,188)
Materials and supplies	(28,402)	(41,273)	(18,885)
Fuel and natural gas inventory	(1,526)	6,565	(34,682)
Prepayments and other	(8,873)	(33,402)	4,186
Accounts payable	79,184	(244,030)	237,260
Taxes payable	2,453	(13,471)	(11,300)
Other	23,220	11,408	18,215
Net cash provided by (used in) operating activities	822,823	1,053,395	769,618
Investing Activities:
Construction expenditures - excluding equity AFUDC	(1,609,715)	(1,466,565)	(1,004,713)
Other	1,872	14,047	(567)
Net cash provided by (used in) investing activities	(1,607,843)	(1,452,518)	(1,005,280)
Financing Activities:
Change in short-term debt, net	(219,700)	122,500	301,300
Dividends paid	(175,861)	(99,760)	(16,230)
Capital contribution	292,800	0	0
Proceeds from long-term debt and bonds issued	793,892	396,488	448,075
Redemption of bonds and notes	0	0	(450,000)
Other	20,015	25,685	18,152
Net cash provided by (used in) financing activities	711,146	444,913	301,297
Net increase (decrease) in cash, cash equivalents, and restricted cash	(73,874)	45,790	65,635
Cash, cash equivalents, and restricted cash at beginning of period	214,575	168,785	103,150
Cash, cash equivalents, and restricted cash at end of period	140,701	214,575	168,785
Supplemental cash flow information:
Cash payments for interest (net of capitalized interest)	376,317	339,677	320,656
Cash payments (refunds) for income taxes	37,065	71,817	46,785
Non-cash financing and investing activities:
Accounts payable for capital expenditures eliminated from cash flow	110,311	97,892	68,357
Seller financing accrued liabilities for capital expenditures eliminated from cash flow	1,700	21,739	0
Capital expenditures due to change in ARO estimate eliminated from cash flow	20,255	(2,206)	1,520
Subsidiaries [Member]
Operating Activities:
Net Income (Loss)	346,148	131,059	490,952
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	781,325	744,629	657,349
Conservation amortization	137,147	121,340	116,942
Deferred income taxes and tax credits, net	(10,232)	(120,394)	(2,103)
Net unrealized (gain) loss on derivative instruments	(33,911)	284,495	(261,177)
AFUDC - equity	(59,466)	(39,012)	(28,310)
Other non-cash	11,971	(539)	(6,005)
Funding of pension liability	(18,000)	(18,000)	(18,000)
Regulatory assets and liabilities	(89,838)	153,069	(90,335)
Purchased gas adjustment	(73,426)	152,763	37,256
GHG emission allowances	(154,728)	(129,195)	0
Other long term assets and liabilities	(1,058)	(14,247)	(14,359)
Change in certain current assets and liabilities:
Accounts receivable and unbilled revenue	(22,687)	136,711	(252,308)
Materials and supplies	(28,402)	(41,273)	(18,885)
Fuel and natural gas inventory	(1,392)	6,057	(33,654)
Prepayments and other	(8,876)	(33,383)	4,186
Accounts payable	78,216	(240,714)	228,635
Taxes payable	2,979	(13,697)	(16,934)
Other	23,318	11,391	24,211
Net cash provided by (used in) operating activities	879,088	1,091,060	817,461
Investing Activities:
Construction expenditures - excluding equity AFUDC	(1,608,947)	(1,465,925)	(1,000,810)
Other	1,872	14,047	(567)
Net cash provided by (used in) investing activities	(1,607,075)	(1,451,878)	(1,001,377)
Financing Activities:
Change in short-term debt, net	(296,600)	(20,400)	217,000
Dividends paid	(153,996)	(96,004)	(35,396)
Capital contribution	292,800	100,000	50,000
Proceeds from long-term debt and bonds issued	793,892	396,488	0
Other	20,009	25,701	21,950
Net cash provided by (used in) financing activities	656,105	405,785	253,554
Net increase (decrease) in cash, cash equivalents, and restricted cash	(71,882)	44,967	69,638
Cash, cash equivalents, and restricted cash at beginning of period	210,852	165,885	96,247
Cash, cash equivalents, and restricted cash at end of period	138,970	210,852	165,885
Supplemental cash flow information:
Cash payments for interest (net of capitalized interest)	276,081	253,835	233,746
Cash payments (refunds) for income taxes	67,888	116,795	93,058
Non-cash financing and investing activities:
Accounts payable for capital expenditures eliminated from cash flow	110,311	97,892	68,357
Seller financing accrued liabilities for capital expenditures eliminated from cash flow	1,700	21,739	0
Capital expenditures due to change in ARO estimate eliminated from cash flow	$ 20,255	$ (2,206)	$ 1,520

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2024
Accounting Policies [Abstract]
Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation Puget Energy is an energy services holding company that owns Puget Sound Energy (PSE). PSE is a public utility incorporated in the state of Washington that furnishes electric and natural gas services in a territory covering approximately 6,000 square miles, primarily in the Puget Sound region. Puget Energy also has a wholly-owned non-regulated subsidiary, Puget LNG, LLC (Puget LNG), which has the sole purpose of owning and operating the non-regulated activity of the Tacoma liquefied natural gas (LNG) facility. PSE and Puget LNG are considered related parties with similar ownership by Puget Energy. Therefore, capital and operating costs that are incurred by PSE and allocated to Puget LNG are related party transactions by nature. In 2009, Puget Holdings, LLC (Puget Holdings), owned by a consortium of long-term infrastructure investors, completed its merger with Puget Energy (the merger). As a result of the merger, all of Puget Energy’s common stock is indirectly owned by Puget Holdings. The acquisition of Puget Energy was accounted for in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 805, “Business Combinations,” as of the date of the merger. ASC 805 requires the acquirer to recognize and measure identifiable assets acquired and liabilities assumed at fair value as of the merger date. The consolidated financial statements of Puget Energy reflect the accounts of Puget Energy and its subsidiaries. PSE’s consolidated financial statements include the accounts of PSE and its subsidiary. Puget Energy and PSE are collectively referred to herein as “the Company”. The consolidated financial statements are presented after elimination of all significant intercompany items and transactions. PSE’s consolidated financial statements continue to be accounted for on a historical basis and do not include any ASC 805. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Utility Plant Puget Energy and PSE capitalize, at original cost, additions to utility plant, including renewals and betterments. Costs include indirect costs such as engineering, supervision, certain taxes, pension and other employee benefits and an allowance for funds used during construction (AFUDC). Replacements of minor items of property are included in maintenance expense. When the utility plant is retired and removed from service, the original cost of the property is charged to accumulated depreciation and costs associated with removal of the property, less salvage, are charged to the cost of removal regulatory liability. Construction Work in Progress Construction work in progress represents construction materials, progress payments on major equipment contracts, engineering costs, AFUDC and other costs directly associated with construction projects. Such costs classified as construction work in progress are included within utility plant on the balance sheet. At completion of such projects, these costs are transferred to utility plant in service. Capitalized costs associated with construction activities are charged to operations and maintenance expenses when recoverability is no longer probable. Planned Major Maintenance Planned major maintenance is an activity that typically occurs when PSE overhauls or substantially upgrades various systems and equipment on a scheduled basis. Costs related to planned major maintenance are deferred and amortized to the next scheduled major maintenance. This accounting method also follows the Washington Commission regulatory treatment related to these generating facilities. Other Property and Investments For PSE, the costs of other property and investments (i.e., non-utility) are stated at historical cost. Expenditures for refurbishment and improvements that significantly add to productive capacity or extend useful life of an asset are capitalized. Replacements of minor items are expensed on a current basis. Gains and losses on assets sold or retired, which were previously recorded in utility plant, are apportioned between regulatory assets/liabilities and earnings. However, gains and losses on assets sold or retired, not previously recorded in utility plant, are reflected in earnings. Depreciation and Amortization The Company provides for depreciation and amortization on a straight-line basis. Amortization is recorded for finance leases, intangibles such as certain regulatory assets and liabilities, computer software and franchises. The annual depreciation provision stated as a percent of a depreciable electric utility plant was 3.4%, 3.4%, and 3.4% in 2024, 2023, and 2022, respectively; depreciable natural gas utility plant was 3.2%, 3.2%, and 2.9% in 2024, 2023, and 2022, respectively; and depreciable common utility plant was 6.6%, 6.5% and 7.1% in 2024, 2023, and 2022, respectively. The cost of removal is collected from PSE’s customers through depreciation expense and any excess is recorded as a regulatory liability. Related Party Transactions The Company identified no material related party transactions during the years ended December 31, 2024, December 31, 2023 and December 31, 2022. Tacoma LNG Facility Operational since February 2022, the Tacoma LNG facility at the Port of Tacoma provides peak-shaving services to PSE’s natural gas customers and provides LNG as fuel to transportation customers, particularly in the marine market at a lower cost due to the facility's scale. In December 2019, the Puget Sound Clean Air Agency (PSCAA) issued the air quality permit for the facility, and the Pollution Hearings Control Board of Washington State upheld the approval following extended litigation. Pursuant to an order by the Washington Commission, PSE will be allocated approximately 43.0% of common capital and operating costs, consistent with the regulated portion of the Tacoma LNG facility. The remaining 57.0% of common capital and operating costs of the Tacoma LNG facility will be allocated to Puget LNG. Per this allocation of costs, $234.8 million and $240.5 million of non-utility plant related to Puget LNG's portion of the Tacoma LNG facility is reported in the Puget Energy "Other property and investments" financial statement line item as of December 31, 2024, and December 31, 2023, respectively. Additionally, $25.2 million, $27.5 million, and $11.6 million of operating costs are reported in the Puget Energy "Non-utility expense and other" financial statement line item in 2024, 2023 and 2022, respectively. Further, $229.0 million and $235.6 million of plant in service related to PSE’s portion of the Tacoma LNG facility is reported in the PSE “Utility plant - Natural gas plant” financial statement line item as of December 31, 2024, and December 31, 2023, respectively, as PSE is a regulated entity. Cash and Cash Equivalents Cash and cash equivalents consist of demand bank deposits and short-term highly liquid investments with original maturities of three months or less at the time of purchase. The carrying amounts of cash and cash equivalents are reported at cost and approximate fair value, due to the short-term maturity. Restricted Cash Restricted cash amounts primarily represent cash posted as collateral for derivative contracts as well as funds required to be set aside for contractual obligations related to transmission and generation facilities. Materials and Supplies Materials and supplies are used primarily in the operation and maintenance of electric and natural gas distribution and transmission systems as well as spare parts for combustion turbines used for the generation of electricity. The Company records these items at weighted-average cost. Fuel and Natural Gas Inventory Fuel and natural gas inventory is used in the generation of electricity and for future sales to the Company’s natural gas customers. Fuel inventory consists of coal, diesel and natural gas used for generation. Natural gas inventory consists of natural gas and LNG held in storage for future sales. The Company records fuel inventory and natural gas inventory for unregulated operations at the lower of cost or net realizable value and natural gas inventory for regulated operations at average cost. Regulatory Assets and Liabilities PSE accounts for its regulated operations in accordance with ASC 980, “Regulated Operations” (ASC 980). ASC 980 requires PSE to defer certain costs or losses that would otherwise be charged to expense, if it is probable that future rates will permit recovery of such costs. It similarly requires deferral of revenues or gains that are expected to be returned to customers in the future. Accounting under ASC 980 is appropriate as long as rates are established by or subject to approval by independent third-party regulators; rates are designed to recover the specific enterprise’s cost of service; and in view of demand for service, it is reasonable to assume that rates set at levels that will recover costs can be charged to and collected from customers. In most cases, PSE classifies regulatory assets and liabilities as long-term when amortization periods extend longer than one year. For further details regarding regulatory assets and liabilities, see Note 4, "Regulation and Rates" to the consolidated financial statements included in Item 8 of this report. Puget Energy recorded regulatory assets and liabilities at the time of the merger related to power purchase contracts. Greenhouse Gas Emission Allowances PSE is required to obtain emission allowances or offset credits for GHG emissions associated with electricity it generates or imports into Washington and natural gas supplied to customers in accordance with the cap-and-invest program included in the CCA. PSE records allocated and purchased emission allowances at cost, similar to an inventory method, and includes purchased emissions allowances in current assets and long-term assets reported in the "GHG emission allowances" line item on the consolidated balance sheets. PSE measures the compliance obligation at the weighted average cost of allowances held plus the fair value of additional allowances required to satisfy the obligation after adjustment for applicable no-cost allowances received. PSE includes the obligation in current liabilities and long-term liabilities reported in the "Compliance obligations" line item on the consolidated balance sheets based on the dates the allowances are to be surrendered. Consistent with ASC 980, PSE defers costs and revenues associated with the cap-and-invest program through regulatory assets and liabilities. Allowance for Funds Used During Construction AFUDC represents the cost of both the debt and equity funds used to finance utility plant additions during the construction period. The amount of AFUDC recorded in each accounting period varies depending primarily upon the level of construction work in progress and the rate used. AFUDC is capitalized as a part of the cost of utility plant; the debt portion is credited to interest expense, while the equity portion is credited to other income. Cash inflow related to AFUDC does not occur until these charges are reflected in rates. The Washington Commission authorized an AFUDC rate, which is calculated using its allowed rate of return for utility plant additions. The AFUDC rate authorized was 7.39% effective October 1, 2020 for natural gas and October 15, 2020 for electric. Per the 2022 GRC, the AFUDC rate authorized is 7.16% effective January 7, 2023 for natural gas and January 11, 2023 for electric. Per the 2024 GRC, the AFUDC rate authorized is 7.52% in 2025 and 7.64% in 2026 effective January 29, 2025. To the extent amounts calculated using this rate exceed the AFUDC calculated rate using the FERC formula, PSE capitalizes the excess as a deferred asset, crediting other income. The deferred asset is being amortized over the average useful life of PSE’s non-project electric utility plant, which is approximately 30 years. Revenue Recognition Operating utility revenue is recognized when the basis of services is rendered, which includes estimated unbilled revenue. Revenue from retail sales is billed based on tariff rates approved by the Washington Commission. PSE's estimate of unbilled revenue is based on a calculation using meter readings from its automated meter reading system. The estimate calculates unbilled usage at the end of each month as the difference between the customer meter readings on the last day of the month and the last customer meter readings billed. The unbilled usage is then priced at published rates for each tariff rate schedule to estimate the unbilled revenues by customer. PSE collected Washington excise taxes (which are a component of general retail customer rates) and municipal taxes totaling $329.9 million, $319.1 million and $292.8 million for 2024, 2023, and 2022, respectively. The Company reports the collection of such taxes on a gross basis in operation revenue and as expense in taxes other than income taxes in the accompanying consolidated statements of income. PSE's electric and natural gas operations contain a revenue decoupling mechanism under which PSE's actual energy delivery revenues related to electric transmission and distribution, natural gas operations and general administrative costs are compared with authorized revenues allowed under the mechanism. The mechanism mitigates volatility in revenue and gross margin erosion due to weather and energy efficiency. Any differences in revenue are deferred to a regulatory asset for under recovery or regulatory liability for over recovery under alternative revenue recognition standard. Revenue is recognized under this program when deemed collectible within 24 months based on alternative revenue recognition guidance. Decoupled rate increases are effective May 1 of each year subject to a soft rate cap of total revenue for decoupled rate schedules, where rate cap is applied to under-collected revenue and any over-collected revenues are passed back to customers at 100%. Any excess under-recovered revenue above the rate cap will be included in the following year's decoupled rate and the Company will only be able to recognize revenue below the rate cap of total revenue for decoupled rate schedules. For revenue deferrals exceeding the annual rate cap of total revenue for decoupled rate schedules, the Company will assess the excess amount to determine its ability to be collected within 24 months per GAAP rules. The soft rate cap test, which limits the amount of revenues PSE can collect in its annual filings, is 5.0% for natural gas customers and 3.0% for electric customers. The Company will not record any decoupling revenue that is expected to take longer than 24 months to collect following the end of the annual period in which the revenues would have otherwise been recognized. Once determined to be collectible within 24 months, any previously non-recognized amounts will be recognized. Revenues associated with energy costs under the PCA mechanism and PGA mechanism are excluded from the decoupling mechanism. Allowance for Credit Losses The Company measures expected credit losses on trade receivables on a collective basis by receivable type, which include electric retail receivables, gas retail receivables, and electric wholesale receivables. The estimate of expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. The following table presents the activity in the allowance for credit losses for accounts receivable at December 31, 2024, and 2023: Puget Energy and (Dollars in Thousands) Year Ended December 31, Allowance for credit losses: 2024 2023 Beginning balance $ 38,211 $ 41,962 Provision for credit loss expense 1 43,573 34,724 Receivables charged-off (41,348) (38,475) Total ending allowance balance $ 40,436 $ 38,211 _____________ 1 $37.1 million and $17.1 million of provision related to balances of deferred costs specific to COVID-19 as of December 31, 2024 and 2023, respectively. Self-Insurance PSE is self-insured for storm damage and certain environmental contamination associated with current operations occurring on PSE-owned property. In addition, PSE is required to meet a deductible for a portion of the risk associated with comprehensive liability, workers’ compensation claims and catastrophic property losses other than those which are storm related. The cumulative annual cost threshold for the storm loss deferral mechanism under the 2017 GRC is $10.0 million. Under the 2024 GRC, the cumulative annual cost threshold for the storm loss deferral mechanism is $9.4 million in 2025 and $9.6 million in 2026. Additionally, costs may only be deferred if the outage meets the Institute of Electrical and Electronics Engineers outage criteria for system average interruption duration index and qualifying costs exceed $0.5 million per qualified storm. Federal Income Taxes For presentation in Puget Energy's and PSE’s separate financial statements, income taxes are allocated to the subsidiaries on the basis of separate company computations of tax, modified by allocating certain consolidated group limitations which are attributed to the separate company. Taxes payable or receivable are settled with Puget Holdings, which is the ultimate taxpayer. Natural Gas Off-System Sales and Capacity Release PSE contracts for firm natural gas supplies and holds firm transportation and storage capacity sufficient to meet the expected peak winter demand for natural gas by its firm customers. Due to the variability in weather, winter peaking consumption of natural gas by most of its customers and other factors, PSE holds contractual rights to natural gas supplies and transportation and storage capacity in excess of its average annual requirements to serve firm customers on its distribution system. For much of the year, there is excess capacity available for third-party natural gas sales, exchanges and capacity releases. PSE sells excess natural gas supplies, enters into natural gas supply exchanges with third parties outside of its distribution area and releases to third parties excess interstate natural gas pipeline capacity and natural gas storage rights on a short-term basis to mitigate the costs of firm transportation and storage capacity for its core natural gas customers. The proceeds from such activities, net of transactional costs, are accounted for as reductions in the cost of purchased natural gas and passed on to customers through the PGA mechanism, with no direct impact on net income. As a result, PSE nets the sales revenue and associated cost of sales for these transactions in purchased natural gas. As part of the Company’s electric operations, PSE purchases natural gas for its gas-fired generation facilities. The projected volume of natural gas for power is relative to the price of natural gas. Based on the market prices for natural gas, PSE may use the natural gas it has already purchased to generate power or PSE may sell the already purchased natural gas. The net proceeds from selling natural gas, previously purchased for power generation, are accounted for in electric operating revenue and are included in the PCA mechanism. Accounting for Derivatives ASC 815, "Derivatives and Hedging" (ASC 815), requires that all contracts considered to be derivative instruments be recorded on the balance sheet at their fair value unless the contracts qualify for an exception. PSE enters into derivative contracts to manage its energy resource portfolio and interest rate exposure including forward physical and financial contracts and swaps. Some of PSE’s physical electric supply contracts qualify for the NPNS exception to derivative accounting rules. PSE may enter into financial fixed price contracts to economically hedge the variability of certain index-based contracts. Those contracts that do not meet the NPNS exception are marked-to-market to current earnings in the statements of income, subject to deferral under ASC 980, for natural gas related derivatives due to the PGA mechanism. On December 19, 2024, the Washington Commission approved the Company's accounting petition in Docket No. UE-240773 to defer any incurred unrealized gains or losses on derivative instruments entered into to serve electric customers, and as such PSE has recognized regulatory assets and/or liabilities, thus deferring the unrealized gains or losses. As of December 31, 2024, the fair value of these derivatives were recorded on the Company's balance sheet as a derivative asset of $38.8 million and a derivative liability of $389.9 million. The difference of $351.1 million has been recorded as a regulatory asset in accordance with the accounting treatment approved by the Washington Commission. Fair Value Measurements of Derivatives ASC 820, “Fair Value Measurements and Disclosures” (ASC 820), defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). As permitted under ASC 820, the Company utilizes a mid-market pricing convention (the mid-point price between bid and ask prices) as a practical expedient for valuing the majority of its assets and liabilities measured and reported at fair value. The Company utilizes market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. The Company primarily applies the market approach for recurring fair value measurements as it believes that approach is used by market participants for these types of assets and liabilities. Accordingly, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. The Company values derivative instruments based on daily quoted prices from an independent external pricing service. When external quoted market prices are not available for derivative contracts, the Company uses a valuation model that uses volatility assumptions relating to future energy prices based on specific energy markets and utilizes externally available forward market price curves. All derivative instruments are sensitive to market price fluctuations that can occur on a daily basis. For additional information, see Note 11, "Fair Value Measurements" to the consolidated financial statements included in Item 8 of this report. Debt-Related Costs Debt premiums, discounts, expenses and amounts received or incurred to settle hedges are amortized over the life of the related debt for the Company. The premiums and costs associated with reacquired debt are deferred and amortized over the life of the related new issuance, in accordance with ratemaking treatment for PSE and presented net of long-term liabilities on the balance sheet. Leases PSE determines if an arrangement is, or contains, a lease at inception of the contract. If the arrangement is, or contains a lease, PSE assesses whether the lease is operating or financing for income statement and balance sheet classification. Operating leases are included in operating lease right-of-use (ROU) assets, operating lease current liabilities, and operating lease liabilities in our consolidated balance sheets. Finance leases are included in utility plant, other current liabilities, and finance lease liabilities in our consolidated balance sheets. ROU assets represent the right to use an underlying asset for the lease term, and consist of the amount of the initial measurement of the lease liability, any lease payments made to the lessor at or before the commencement date, minus any lease incentives received, and any initial direct costs incurred by the lessee. Lease liabilities represent our obligation to make lease payments arising from the lease and are measured at present value of the lease payments not yet paid, discounted using the discount rate for the lease, determined based on PSE's incremental borrowing rate, at commencement. As most of PSE's leases do not provide an implicit interest rate, PSE uses the incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. For fleet, IT and wind farm land leases, this rate is applied using a portfolio approach. The lease terms may include options to extend or terminate the lease when it is reasonably certain that PSE will exercise that option. On the statement of income, operating leases are generally accounted for under a straight-line expense model, while finance leases, which were previously referred to as capital leases, are generally accounted for under a financing model. Consistent with the previous lease guidance, however, the standard allows rate-regulated utilities to recognize expense consistent with the timing of recovery in rates. PSE has lease agreements with lease and non-lease components. Non-lease components comprise common area maintenance and utilities, and are accounted for separately from lease components. Variable Interest Entities In April 2017, PSE entered into a power purchase agreement (PPA) with Skookumchuck Wind Energy Project, LLC (Skookumchuck) pursuant to which Skookumchuck would develop a wind generation facility and sell bundled energy and associated attributes, namely renewable energy certificates (RECs), to PSE over a term of 20 years. Skookumchuck commenced commercial operation in November 2020. In May 2020, PSE entered into a PPA with Golden Hills Wind Farm, LLC (Golden Hills) pursuant to which Golden Hills would develop a wind generation facility and sell bundled energy and associated attributes, namely RECs, to PSE over a term of 20 years. On April 29, 2022, Golden Hills commenced commercial operations. In February 2021, PSE entered into a PPA with Clearwater Wind Project, LLC (Clearwater) in which Clearwater would develop a wind generation facility and sell energy and associated attributes to PSE over a term of 25 years. On November 8, 2022, Clearwater commenced commercial operations. For each of the aforementioned PPAs, PSE has no equity investment in the generation facilities, but is the only customer of each facility. PSE has concluded that Skookumchuck, Golden Hills and Clearwater represent VIE and that PSE is not the primary beneficiary of these VIEs since it does not control the commercial and operating activities of the facilities. Additionally, PSE does not have the obligation to absorb losses or receive benefits. As a result, PSE does not consolidate the VIEs. Purchased energy of $88.9 million, $86.0 million and $38.6 million
Related Party Transactions	Related Party Transactions

New Accounting Pronouncements

New Accounting Pronouncements	12 Months Ended
	Dec. 31, 2024
Accounting Standards Update and Change in Accounting Principle [Abstract]
New Accounting Pronouncements	New Accounting Pronouncements Recently Adopted Accounting Guidance Reference Rate Reform In March 2020, the FASB issued Accounting Standards Updated (ASU) 2020-04, "Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting ”. ASU 2020-04 provides temporary optional expedients and exceptions to the current guidance on contract modifications to ease the financial reporting burdens related to the expected market transition from London Interbank Offered Rate (LIBOR) and other interbank offered rates to alternative reference rates. In December 2022, the FASB issued ASU 2022-06, "Reference Rate Reform (Topic 848): Deferral of the Sunset Date of Topic 848" . ASU 2022-06 postponed the sunset date of Topic 848 from December 31, 2022 to December 31, 2024. As of December 31, 2024, the Company is not aware of any current agreements that reference LIBOR and thus, has not utilized any practical expedients. Reportable Segment Disclosures In November 2023, the FASB issued ASU 2023-07, "Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures". ASU 2023-07 is intended to improve the disclosures for reportable segments and provide more detailed information about a reportable segment's expenses. This requires disclosure of significant segment expense categories, amounts for each reportable segment, disclosure of the title and position of the Chief Operating Decision Maker and how they use the measure of the segments' profit or loss to assess performance and allocate resources. ASU 2023-07 is effective for the Company in fiscal years beginning after December 15, 2023, and interim periods in fiscal years beginning after December 15, 2024. As of December 31, 2024, the Company's disclosures are consistent with the amendment. Income Tax Disclosures In December 2023, the FASB issued ASU 2023-09, "Income Taxes (Topic 740): Improvements to Income Tax Disclosures". ASU 2023-09 will require disclosure of specific categories in a tabular rate reconciliation using both percentages and currency amounts, and provide additional information for reconciling items that meet a quantitative threshold. Further requirements include a qualitative description of the tax jurisdictions, an explanation of the reconciling items disclosed and disclosure regarding income taxes paid. ASU 2023-09 eliminates the requirement to disclose the nature and estimate of range in unrecognized tax benefits and disclosures of the cumulative amount of each type of temporary difference when a deferred tax liability is not recognized. ASU 2023-09 will be effective for the Company in annual periods beginning after December 15, 2024. As of December 31, 2024, the Company's disclosures are consistent with the amendment. Accounting Standards Issued but Not Yet Adopted Income Statement Reporting Comprehensive Income Disclosures In November 2024, the FASB issued ASU 2024-03, " Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures

Revenue (Notes)

Revenue (Notes)	12 Months Ended
	Dec. 31, 2024
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer	Revenue The following tables present disaggregated revenue from contracts with customers, and other revenue by major source for the years ended December 31, 2024, December 31, 2023, and December 31, 2022: Puget Energy and (Dollars in Thousands) Year Ended December 31, 2024 Revenue from contracts with customers: Electric Natural Gas Other 1 Total Retail Residential $ 1,677,599 $ 796,889 $ — $ 2,474,488 Commercial 1,159,596 367,988 — 1,527,584 Industrial 131,869 26,764 — 158,633 Other 23,601 — — 23,601 Wholesale 286,364 — — 286,364 Transmission and transportation 33,911 30,874 — 64,785 Miscellaneous 2 35,274 246,708 34,950 316,932 Total revenue from contracts with customers $ 3,348,214 $ 1,469,223 $ 34,950 $ 4,852,387 Total other revenue 3 (15,519) 19,347 — 3,828 Total operating revenue $ 3,332,695 $ 1,488,570 $ 34,950 $ 4,856,215 _____________ 1. Other includes $34.7 million of Puget LNG revenues recorded at Puget Energy. 2. Miscellaneous natural gas revenue includes $253.0 million for the regulatory offset of CCA auction proceeds passed back to customers. 3. Total other revenue includes revenues from derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Puget Energy and (Dollars in Thousands) Year Ended December 31, 2023 Revenue from contracts with customers: Electric Natural Gas Other 1 Total Retail Residential $ 1,514,149 $ 851,906 $ — $ 2,366,055 Commercial 1,071,385 383,431 — 1,454,816 Industrial 123,548 29,149 — 152,697 Other 21,199 — — 21,199 Wholesale 498,251 — — 498,251 Transmission and transportation 46,141 24,265 — 70,406 Miscellaneous 2 25,231 94,193 47,431 166,855 Total revenue from contracts with customers $ 3,299,904 $ 1,382,944 $ 47,431 $ 4,730,279 Total other revenue 3 45,963 40,332 — 86,295 Total operating revenue $ 3,345,867 $ 1,423,276 $ 47,431 $ 4,816,574 _____________ 1. Other includes $31.0 million of Puget LNG revenues recorded at Puget Energy 2. Miscellaneous natural gas revenue includes $98.4 million for the regulatory offset of CCA auction proceeds passed back to customers. 3. Total other revenue includes revenues from derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Puget Energy and (Dollars in Thousands) Year Ended December 31, 2022 Revenue from contracts with customers: Electric Natural Gas Other 1 Total Retail Residential $ 1,381,858 $ 808,376 $ — $ 2,190,234 Commercial 981,170 352,243 — 1,333,413 Industrial 116,712 25,096 — 141,808 Other 18,759 — — 18,759 Wholesale 319,380 — — 319,380 Transmission and transportation 47,027 20,332 — 67,359 Miscellaneous 13,065 718 50,069 63,852 Total revenue from contracts with customers $ 2,877,971 $ 1,206,765 $ 50,069 $ 4,134,805 Total other revenue 2 83,486 2,871 — 86,357 Total operating revenue $ 2,961,457 $ 1,209,636 $ 50,069 $ 4,221,162 _____________ 1. Other includes $5.0 million of Puget LNG revenues recorded at Puget Energy 2. Total other revenue includes revenues from derivatives, PTC deferral revenue and alternative revenue programs that are not considered revenues from contracts with customers. Revenue at PSE is recognized when performance obligations under the terms of a contract or tariff with our customers are satisfied. Performance obligations are satisfied generally through performance of PSE's obligation over time or with transfer of control of electric power, natural gas, and other revenue from contracts with customers. Revenue is measured as the amount of consideration expected to be received in exchange for transferring goods and services. Electric and Natural Gas Retail Revenue Electric and natural gas retail revenue consists of tariff-based sales of electricity and natural gas to PSE's customers. For tariff contracts, PSE has elected the portfolio approach practical expedient model to apply the revenue from contracts with customers to groups of contracts. The Company determined that the portfolio approach will not differ from considering each contract or performance obligation separately. Electric and natural gas tariff contracts include the performance obligation of standing ready to perform electric and natural gas services. The electricity and natural gas the customer chooses to consume is considered an option and is recognized over time using the output method when the customer simultaneously consumes the electricity or natural gas. PSE has elected the right to invoice practical expedient for unbilled retail revenue. The obligation of standing ready to perform electric service and the consumption of electricity and natural gas at market value implies a right to consideration for performance completed to date. The Company believes that tariff prices approved by the Washington Commission represent stand-alone selling prices for the performance obligations under ASC 606 "Revenue from Contracts with Customers". PSE collects Washington State excise taxes (which are a component of general retail customer rates) and municipal taxes and presents the taxes on a gross basis, as PSE is the taxpayer for those excise and municipal taxes. Other Revenue from Contracts with Customers Other revenue from contracts with customers is primarily comprised of electric transmission, natural gas transportation, biogas, and wholesale revenue sold on an intra-month basis. Electric Transmission and Natural Gas Transportation Transmission and transportation tariff contracts include the performance obligation to transmit and transport electricity or natural gas. Transfer of control and recognition of revenue occurs over time as the customer simultaneously receives the transmission and transportation services. Measurement of satisfaction of this performance obligation is determined using the output method. Similar to retail revenue, the Company utilizes the right to invoice practical expedient as PSE’s right to consideration is tied directly to the value of power and natural gas transmitted and transported each month. The price is based on the tariff rates that were approved by the Washington Commission or the FERC and, therefore, corresponds directly to the value to the customer for performance completed to date. Biogas Biogas is a renewable natural gas fuel that PSE purchases and sells along with the renewable green attributes derived from the renewable natural gas. Biogas contracts include the performance obligations of biogas and renewable credit delivery upon PSE receiving produced biogas from its supplier. Transfer of control and recognition of revenue occurs at a point in time as biogas is considered a storable commodity and may not be consumed as it is delivered. Wholesale Wholesale revenue at PSE includes sales of electric power and non-core natural gas to other utilities or marketers. Wholesale revenue contracts include the performance obligation of physical electric power or natural gas. There are typically no added fixed or variable amounts on top of the established rate for power or natural gas and contracts always have a stated, fixed quantity of power or natural gas delivered. Transfer of control and recognition of revenue occurs at a point in time when the customer takes physical possession of electric power or natural gas. Non-core gas consists of natural gas supply in excess of natural gas used for generation, sold to third parties to mitigate the costs of firm transportation and storage capacity for its core natural gas customers. PSE reports non-core gas sold net of costs, as PSE does not take control of the natural gas but is merely an agent within the market that connects a seller to a purchaser. Other Revenue In accordance with ASC 606, PSE separately presents revenue not collected from contracts with customers that falls under other accounting guidance. Transaction Price Allocated to Remaining Performance Obligations In December 2020, Puget LNG entered into a contract with one customer where Puget LNG is selling LNG over a 10-year delivery period beginning April 1, 2024. The contract requires the customer to purchase a minimum annual quantity even if the customer does not take delivery. The price of the LNG includes a fixed charge, a fuel charge that includes both a market index and fixed margin component and other variable consideration. The fixed transaction price is allocated to the remaining performance obligations which is determined by the fixed charge components multiplied by the outstanding minimum annual quantity. Based on management’s best estimate, the Company expects to recognize this revenue over the following time periods: Puget Energy (Dollars in Thousands) 2025 2026 2027 2028 2029 Thereafter Total Remaining Performance Obligations $ 19,554 $ 19,454 $ 19,454 $ 19,454 $ 19,454 $ 82,681 $ 180,051

Regulation and Rates

Regulation and Rates	12 Months Ended
	Dec. 31, 2024
Regulated Operations [Abstract]
Regulation and Rates	4) Regulation and Rates Regulatory Assets and Liabilities Regulatory accounting allows PSE to defer certain costs that would otherwise be charged to expense, if it is probable that future rates will permit recovery of such costs. It similarly requires deferral of revenues or gains that are expected to be returned to customers in the future. The net regulatory assets and liabilities at December 31, 2024, and 2023, are included in the following tables: Puget Sound Energy Remaining Amortization Period December 31, (Dollars in Thousands) 2024 2023 PCA unrealized loss N/A $ 284,166 $ — Environmental remediation (a) 180,245 182,697 Storm damage costs electric 1 to 4 years 120,431 95,754 Automated meter reading 19 years 98,572 104,159 Energy conservation costs (a) 75,373 37,560 PGA unrealized loss N/A 66,929 80,376 PCA mechanism N/A 61,202 48,427 Baker Dam licensing operating and maintenance costs (b) 56,201 55,641 Deferred Washington Commission AFUDC 30 years 55,427 58,648 Decoupling deferrals and interest Less than 2 years 51,838 31,398 Chelan PUD contract initiation 6.8 years 48,435 55,523 Climate Commitment Act auction proceeds N/A 43,538 186,550 Washington Commission LNG N/A 38,070 42,247 Washington Commission COVID-19 N/A 37,089 17,097 Lower Snake River 12.4 years 35,429 43,220 Unamortized loss on reacquired debt 3 to 43 years 29,680 31,626 Regulatory filing fee deferral (c) 2 years 26,543 14,582 Various other regulatory assets (a) 107,325 126,473 Total PSE regulatory assets $ 1,416,493 $ 1,211,978 Cost of removal (d) $ (748,095) $ (682,058) Deferred income taxes (e) N/A (722,558) (761,621) Repurposed production tax credits N/A (110,746) (126,482) Climate Commitment Act recovery N/A (97,694) (84,485) Decoupling liability Less than 2 years (63,890) (60,664) PGA liability 2 years (58,657) (132,082) Bill discount rate deferral N/A (20,567) (6,579) Various other regulatory liabilities (a) (33,435) (60,925) Total PSE regulatory liabilities $ (1,855,642) $ (1,914,896) PSE net regulatory assets (liabilities) $ (439,149) $ (702,918) __________________ (a) Amortization periods vary depending on the timing of underlying transactions. (b) The FERC license requires PSE to incur various O&M expenses over the life of the 50 year license for Baker. The regulatory asset represents the net present value of future expenditures and will be offset by actual costs incurred. (c) Amortization period approved in 2024 GRC, beginning January 29, 2025. (d) The balance is dependent upon the cost of removal of underlying assets and the life of utility plant. (e) For additional information, see Note 14,"Income Taxes" to the consolidated financial statements included in Item 8 of this report. Puget Energy Remaining Amortization Period December 31, (Dollars in Thousands) 2024 2023 Total PSE regulatory assets (a) $ 1,416,493 $ 1,211,978 Puget Energy acquisition adjustments: Regulatory assets related to power contracts 3 to 30 years 4,779 6,266 Total Puget Energy regulatory assets $ 1,421,272 $ 1,218,244 Total PSE regulatory liabilities (a) $ (1,855,642) $ (1,914,896) Puget Energy acquisition adjustments: Deferred income taxes 651 660 Regulatory liabilities related to power contracts 3 to 30 years (30,566) (46,924) Various other regulatory liabilities Varies (1,193) (1,264) Total Puget Energy regulatory liabilities $ (1,886,750) $ (1,962,424) Puget Energy net regulatory asset (liabilities) $ (465,478) $ (744,180) ____________________ (a) Puget Energy’s regulatory assets and liabilities include purchase accounting adjustments under ASC 805. If the Company determines that it no longer meets the criteria for continued application of ASC 980, the Company would be required to write off its regulatory assets and liabilities related to those operations not meeting ASC 980 requirements. Discontinuation of ASC 980 could have a material impact on the Company's financial statements. In accordance with guidance provided by ASC 410, “Asset Retirement and Environmental Obligations (ARO),” PSE reclassified from accumulated depreciation to a regulatory liability $748.1 million and $682.1 million in 2024 and 2023, respectively, for the cost of removal of utility plant. These amounts are collected from PSE’s customers through depreciation rates. General Rate Case Filing PSE filed a GRC, which included a two year MYRP with the Washington Commission on February 15, 2024, requesting an overall increase in electric and natural gas rates of 6.7% and 19.0% respectively in rate year one (expected to approximate calendar year 2025) and 8.5% and 2.1%, respectively in rate year two (expected to approximate calendar year 2026). PSE requested a return on equity of 9.95% for rate year one beginning in 2025 and 10.5% for rate year two, beginning in 2026. PSE requested an overall rate of return of 7.65% in rate year one and 7.99% in rate year two. The filing requests recovery of forecasted plant additions through 2024 as required by RCW 80.28.425 as well as forecasted plant additions through 2026, the final year of the MYRP. On January 15, 2025, the Washington Commission issued an order on PSE's 2024 GRC that approved a weighted cost of capital of 7.52% in 2025 and 7.64% in 2026, a capital structure of 49.0% in common equity in 2025 and 50.0% in 2026, and a return on equity of 9.8% in 2025 and 9.9% in 2026. On January 28, 2025, the Washington Commission approved PSE's electric and natural gas rates in its compliance filing with an overall net revenue change for electric of $378.2 million or 13.3% in 2025 and $191.0 million or 5.9% in 2026 and an overall net revenue change for natural gas of $110.0 million or 10.6% in 2025 and $20.0 million or 1.8% in 2026, with an effective date of January 29, 2025. PSE filed a petition for reconsideration on January 24, 2025 and multiple parties filed petitions for reconsideration and a motion for clarification on January 27, 2025. The Washington Commission will determine what, if any, further action will be taken with respect to these petitions by March 17, 2025. On April 24, 2024, the Washington Commission issued Final Order 07 under Docket No. UG-230393. The order determined that PSE acted prudently in developing and constructing the Tacoma LNG Facility after the initial decision to build in September 2016. Further, there were two main outcomes that resulted from the order. First, the Washington Commission did not authorize recovery of the portion of the Company’s deferred return on its investment in the Tacoma LNG Facility that was recorded between February 1, 2022, the date the facility was placed into service, and January 11, 2023, the date PSE’s 2022 GRC rates went into effect. Second, the Washington Commission directed PSE to increase the allocation of distribution pipeline investment to Puget LNG. The Washington Commission determined that the allocation should be tied to the relative flow of natural gas across these facilities, resulting in a higher allocation to Puget LNG than was originally filed. On May 3, 2024, PSE made the compliance filing required by Final Order 07. On May 24, 2024, Public Counsel and the Puyallup Tribe of Indians each filed a petition for judicial review of the Washington Commission’s Final Order 07. The petitions were filed in Thurston County Superior Court and are expected to be consolidated. Both petitions allege that the Washington Commission (i) failed to properly apply the updated public interest standard, (ii) failed to disallow all costs related to PSE’s redesign of the pipeline and development of waste gas disposal methods, and (iii) failed to conduct an independent determination of reasonable attorney fees. On December 22, 2022, the Washington Commission issued an order on PSE’s 2022 GRC, which was filed on January 31, 2022, that approved a weighted cost of capital of 7.16%, or 6.62% after-tax, a capital structure of 49.0% in common equity in 2023 and 2024, and a return on equity of 9.4%. On January 6, 2023, the Washington Commission approved PSE’s natural gas rates in its compliance filing with an overall net revenue change of $70.8 million or 6.4% in 2023 and $19.5 million or 1.7% in 2024, with an effective date of January 7, 2023. On January 10, 2023, the Washington Commission approved PSE’s electric rates in its compliance filing with an overall net revenue change of $247.0 million or 10.8% in 2023 and $33.1 million or 1.3% in 2024 with an effective date of January 11, 2023. Per the 2022 GRC Final Order in Docket No. UE-220066, rates approved in PSE's PCORC were set to zero as of January 11, 2023, and PSE agreed not to file a PCORC during 2023 and 2024, the period covered by the two-year rate plan agreed to in the GRC settlement. Per the 2022 GRC Final Order in Docket No. UG-220067, PSE was authorized to seek recovery of the costs related to the Tacoma LNG Facility concurrent with its 2023 PGA filing. Prior rates were subject to the 2019 GRC and included a weighted cost of capital of 7.39% or 6.8% after-tax, and a capital structure of 48.5% in common equity with a return on equity of 9.4%. The annualized overall rate impacts were an electric revenue increase of $48.3 million, or 2.3%, and a natural gas increase of $4.9 million, or 0.6%, effective October 1, 2021. For further information, see Note 4, "Regulation and Rates" to the consolidated financial statements included in Item 8 of the Company's Form 10-K for the period ended December 31, 2022. PCA and PGA Unrealized Loss On December 19, 2024, the Washington Commission approved the Company's accounting petition in Docket No. UE-240773 to offset any derivative assets or liabilities, entered into in order to serve electric customers, with a regulatory asset or liability, thus deferring the unrealized gains or losses. For additional information, see Note 10, "Accounting for Derivative Instruments and Hedging Activities" to the consolidated financial statements included in Item 8 of this report. Climate Commitment Act Deferral On December 29, 2022, PSE filed accounting petitions with the Washington Commission requesting authorization to defer costs and revenues associated with the Company’s compliance with the CCA codified in law within Revised Code of Washington (RCW) 70A.65. On February 28, 2023, in Order 01 under Docket No. UE-220974 and UG-220975, the Washington Commission granted PSE approval to defer the cost of emission allowances to comply with the CCA and the proceeds from no-cost allowances consigned to auction beginning January 1, 2023. On August 3, 2023, the Washington Commission approved PSE's request for CCA rates in Docket No. UG-230470, subject to refund, effective October 1, 2023, to recover the estimated ongoing allowance costs and proportionate pass back of credits to customers from estimated auction proceeds during the period of August 2023 through December 2023. On October 26, 2023, the Washington Commission approved PSE's request for CCA rates in Docket No. UG-230756, subject to refund, effective November 1, 2023, to recover the estimated ongoing allowance costs and proportionate pass back of credits to customers from estimated auction proceeds during the period of January 2023 through September 2023. On November 22, 2023, PSE filed proposed revisions to its natural gas rates to incorporate allowance costs and auction proceeds in Docket UG-230968. In the filing PSE sought to update rates pertaining to amounts deferred from January 2023 through September 2023 and to add new language to the tariff that would enable PSE to fund decarbonization projects using a portion of the projected no cost allowances revenues. The request, as revised by PSE on December 19, 2023, represented a revenue increase of $29.1 million. The Washington Commission suspended the tariff sheets but allowed the rates to go into effect on an interim basis, subject to refund, on January 1, 2024. The Washington Commission had a hearing for the issue of risk sharing of CCA compliance costs on October 9, 2024 and has not yet issued an order. As of December 31, 2024, PSE has not sought cost recovery for its allowance costs for electric operations. The ongoing recovery of allowance costs and pass back of proceeds from the sale of consigned no-cost allowances for PSE's natural gas operations is consistent with the approved accounting petitions in Dockets No. UG-220975 and UG-230471. As of December 31, 2024, PSE recorded a regulatory liability of $97.7 million which represents the amounts to date collected in customer natural gas rates for CCA obligation costs, net of the expense incurred for the purchase of allowances for electric and natural gas operations. Additionally, PSE will continue to consign for auction at least the minimum amount of no-cost emission allowances allocated for natural gas operations in compliance with the CCA, the proceeds of which will continue to be used for the benefit of natural gas customers, as determined by the Washington Commission. PSE does not record a regulatory liability to defer the proceeds until consigned allowances are sold at auction. As of December 31, 2024, PSE recorded a regulatory asset of $43.5 million, which represents the proceeds from the sale of consigned natural gas GHG emission allowances passed back through customer rates, net of proceeds received from the sale of consigned allowances sold at auction. Colstrip Adjustment Rider On September 30, 2024, PSE filed proposed revisions to rates under the Colstrip Adjustment Rider Schedule 141COL with the Washington Commission, seeking to recover actual and forecasted costs for Colstrip Units 3 and 4 for calendar year 2025. The proposed revisions would increase PSE's annual revenues by $4.1 million, or 0.1%. The Washington Commission Staff identified concerns regarding certain capital investments related to the Colstrip coal-fired generating facility, particularly in light of the Clean Energy Transformation Act's mandate to remove coal-fired generation facility costs from rates by December 31, 2025. On December 23, 2024, the Washington Commission issued Order 01, requiring PSE to file revised tariff pages by December 23, 2024, with rates effective January 1, 2025, subject to refund pending final determination. The Washington Commission has set the matter for adjudication and a prehearing conference to set the procedural schedule will be held during the first quarter of 2025. The Washington Commission's order allows the rates to be collected beginning January 1, 2025, but explicitly notes this does not represent a resolution or final determination of any matter raised in Docket No. UE-240729. Revenue Decoupling Adjustment Mechanism PSE performed an analysis to determine if electric and natural gas decoupling revenue deferrals would be collected from customers within 24 months of the annual period, per ASC 980. If not, for GAAP purposes only, PSE would need to record a reserve against the decoupling revenue and regulatory asset balance. Once the reserve is probable of collection within 24 months from the end of the annual period, the reserve can be recognized as decoupling revenue. Based on the analyses as of December 31, 2024, $0.2 million and zero reserve adjustment was recorded to electric and natural gas decoupling as of December 31, 2024 and zero reserve adjustment was recorded to electric and natural gas decoupling as of December 31, 2023. Power Cost Adjustment Mechanism PSE currently has a PCA mechanism that provides for the deferral of power costs that vary from the “power cost baseline” level of power costs. The “power cost baseline” levels are set, in part, based on normalized assumptions about weather and hydroelectric conditions. Excess power costs or savings are apportioned between PSE and its customers pursuant to the graduated scale set forth in the PCA mechanism and will trigger a surcharge or refund when the cumulative deferral trigger is reached. Effective January 1, 2017, the following graduated scale is used in the PCA mechanism: Company’s Share Customers' Share Annual Power Cost Variability Over Under Over Under Over or under collected up to $17 million 100 % 100 % — % — % Over or under collected between $17 million - $40 million 35 50 65 50 Over or under collected beyond $40 million 10 10 90 90 For the year ended December 31, 2024, in its PCA mechanism, PSE under recovered its allowable costs by $123.3 million of which $86.5 million was apportioned to customers and $3.9 million of interest was accrued on the deferred customer balance. This compares to an over recovery of allowable costs of $51.1 million, for the year ended December 31, 2023, of which $24.9 million was apportioned to customers and accrued $3.9 million of interest on the total deferred customer balance. Power Cost Adjustment Clause PSE exceeded the $20.0 million cumulative deferral balance in its PCA mechanism in 2022. During 2022, actual power costs were higher than baseline power costs, thereby creating an under-recovery of $110.1 million. Under the terms of the PCA’s sharing mechanism for under-recovered power costs, PSE absorbed $39.0 million of the under-recovered amount, and customers were responsible for the remaining $71.1 million, or $76.4 million, including interest and adjusted for revenue sensitive items. On April 28, 2023, PSE filed the 2022 PCA report under Docket No. UE-230313 that proposed a recovery of the deferred balance, which included a revenue requirement increase of 0.9% in overall bill for all customers, with rates proposed to go into effect from December 1, 2023 through December 31, 2024. On September 29, 2023, PSE filed its variable power cost rates update as part of the 2022 GRC Order requirement under Docket No. UE-220066. The filing was approved in part on December 22, 2023, with updated rates effective January 1, 2024. PSE exceeded the $20.0 million cumulative deferral balance in its PCA mechanism in 2023. During 2023, actual power costs were lower than baseline power costs, thereby, creating an over-recovery of $51.1 million. Under the terms of the PCA’s sharing mechanism for over-recovered costs, PSE's share of the over-recovery was $26.2 million and customers were due the remaining $24.9 million, or $22.2 million, including interest and adjusted for revenue sensitive items. On April 30, 2024, PSE filed the 2023 PCA compliance report, in Docket No. 240288, that proposed to pass back 2023 deferred balances from October 1, 2024 to December 31, 2025, resulting in credits to customers of $22.2 million. Additionally, PSE requested to recover the forecasted 2024 deferred balance of $98.2 million from October 1, 2024 to December 31, 2025. On September 26, 2024, the Washington Commission approved the filing as proposed with rates going into effect October 1, 2024 and January 1, 2025. Purchased Gas Adjustment Mechanism In October 2022, the Washington Commission approved PSE's request for PGA rates in Docket No. UG-220715, effective November 1, 2022. As part of that filing, PSE requested an annual revenue increase of $155.3 million, where PGA rates, under Schedule 101, increase annual revenue by $142.1 million, and the tracker rates under Schedule 106, increase annual revenue by $13.2 million. In November 2022, the FERC approved a settlement of a counterparty, FERC Docket No. RP17-346. Under the terms, PSE was allocated $24.2 million related to PSE natural gas services which was recorded on December 31, 2022, and included below. The 2022 GRC order requires PSE to amortize the refund in 2023 as a credit against natural gas costs and therefore pass back the refund to customers through the PGA mechanism. On October 26, 2023, the Washington Commission approved PSE's request for PGA rates in Docket No. UG-230769, effective November 1, 2023. As part of that filing, PSE requested an annual revenue decrease of $309.4 million, where PGA rates, under Schedule 101, decrease annual revenue by $93.9 million, and the tracker rates under Schedule 106, decrease annual revenue by $215.5 million. The annual 2023 PGA rate decreases include the aforementioned counterparty settlement pass back of $28.1 million under Supplemental Schedule 106B. On October 24, 2024, the Washington Commission approved PSE's request for PGA rates in Docket No. UG-240708, effective November 1, 2024. As part of that filing, PSE requested an annual overall revenue increase of $124.4 million, where PGA rates, under Schedule 101, decrease annual revenue by $2.6 million and the tracker rates, under Schedule 106, increase annual revenue by $127.0 million. The revenue increase in Schedule 106 is primarily due to the cessation of the counterparty refund of $28.1 million, mentioned above, that was amortized as a credit in 2023 and $142.8 million in commodity deferrals that were passed back to customers. The following table presents the PGA mechanism balances and activity as of December 31, 2024 and December 31, 2023: Puget Energy and (Dollars in Thousands) Year Ended December 31, PGA (liability)/receivable balance and activity 2024 2023 PGA (liability)/receivable beginning balance $ (132,082) $ (3,536) Actual natural gas costs 416,067 404,897 Allowed PGA recovery (336,170) (521,882) Interest (6,472) (7,639) Refund from counterparty settlement — (3,922) PGA (liability)/receivable ending balance $ (58,657) $ (132,082) Storm Loss Deferral Mechanism The Washington Commission has defined deferrable weather-related events and provided that costs in excess of the annual cost threshold may be deferred for qualifying damage costs that meet the modified Institute of Electrical and Electronics Engineers outage criteria for system average interruption duration index. For the year ended December 31, 2024, PSE incurred $74.5 million in weather-related electric transmission and distribution system restoration costs, of which the Company deferred $58.9 million and zero as regulatory assets related to storms that occurred in 2024 and 2023, respectively. This compares to $8.1 million incurred in weather-related electric transmission and distribution system restoration costs for the year ended December 31, 2023, of which the Company deferred zero and $2.1 million as regulatory assets related to storms that occurred in 2023 and 2022, respectively. Under the 2017 GRC Order, the storm loss deferral mechanism approved the following: (i) the cumulative annual cost threshold for deferral of storms under the mechanism at $10.0 million; and (ii) qualifying events where the total qualifying cost is less than $0.5 million will not qualify for deferral and these costs will also not count toward the $10.0 million annual cost threshold. Environmental Remediation The Company is subject to environmental laws and regulations by federal, state and local authorities and is required to undertake certain environmental investigative and remedial efforts as a result of these laws and regulations. The Company has been named by the Environmental Protection Agency (EPA), the WDOE and/or other third parties as potentially responsible or liable at several contaminated sites, including former manufactured gas plant sites. In accordance with the guidance of ASC 450 “Contingencies,” the Company reviews its estimated future obligations and will record adjustments, if any, on a quarterly basis. The adjustments recorded are based on the best estimate or the low end of a range of reasonably possible costs expected to be incurred by the Company based on its currently understood legal exposure at applicable sites. It is reasonably possible that incurred costs exceed the recorded amounts due to changes in laws and/or regulations, higher than expected costs due to changes in labor market or supply chain, evolving technology, unforeseen and/or the discovery of new or additional contamination. The Company currently estimates that a significant portion of its past and future environmental remediation costs are recoverable from insurance companies, from third parties, and/or from customers under a Washington Commission order. The Company is subject to cost-sharing agreements with third parties regarding environmental remediation projects in Seattle, Tacoma, Everett, and Bellingham, Washington. As of December 31, 2024, the Company’s share of future remediation costs is estimated to be approximately $73.0 million. The following table summarizes changes in the Company's environmental remediation regulatory assets for the years ended December 31, 2024, and 2023: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Environmental remediation regulatory asset beginning balance $ 182,697 $ 141,893 Remediation cost amortization, net of recoveries (3,732) (4,521) Changes in estimates 1 1,280 45,325 Environmental remediation regulatory asset ending balance $ 180,245 $ 182,697 _______________ 1 . The 2023 change was driven in significant part by the Quendall Terminals site on Lake Washington in Renton, Washington. The site represents contaminated facilities from a long defunct creosote manufacturer, which had purchased waste products from PSE predecessors. In addition, it was driven by an increase in estimate at the shared site of Gas Works Park on Lake Union in Seattle, Washington, which was previously a gas manufacturing plant. The following table summarizes changes in the Company's environmental remediation liabilities for the years ended December 31, 2024, and 2023: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Environmental remediation liabilities beginning balance $ 180,440 $ 135,052 Payments made, net of recoveries (10) (495) Changes in estimates 1 725 45,883 Environmental remediation liabilities ending balance $ 181,155 $ 180,440 _______________ 1.

Dividend Payment Restrictions

Dividend Payment Restrictions	12 Months Ended
	Dec. 31, 2024
Dividend Payment Restrictions [Abstract]
Dividend Payment Restrictions	Dividend Payment Restrictions The payment of dividends by PSE to Puget Energy is restricted by provisions of certain covenants applicable to long-term debt contained in PSE’s electric and natural gas mortgage indentures. At December 31, 2024, approximately $1.8 billion of unrestricted retained earnings was available for the payment of dividends under the most restrictive mortgage indenture covenant. Pursuant to the terms of the Washington Commission merger order, PSE may not declare or pay dividends if PSE’s common equity ratio, calculated on a regulatory basis, is 44.0% or below except to the extent a lower equity ratio is ordered by the Washington Commission. Also, pursuant to the merger order, PSE may not declare or make any distribution unless on the date of distribution PSE’s corporate credit/issuer rating is investment grade, or, if its credit ratings are below investment grade, PSE’s ratio of earnings before interest, tax, depreciation and amortization (EBITDA) to interest expense for the most recently ended four fiscal quarter periods prior to such date is equal to or greater than 3.0 to 1.0. The common equity ratio, calculated on a regulatory basis, was 48.1% at December 31, 2024, and the EBITDA to interest expense was 4.6 to 1.0 for the twelve months ended December 31, 2024. PSE’s ability to pay dividends is also limited by the terms of its credit facilities, pursuant to which PSE is not permitted to pay dividends during any Event of Default (as defined in the facilities), or if the payment of dividends would result in an Event of Default, such as failure to comply with certain financial covenants. Puget Energy’s ability to pay dividends is also limited by the merger order issued by the Washington Commission. Pursuant to the merger order, Puget Energy may not declare or make a distribution unless on such date Puget Energy’s ratio of consolidated EBITDA to consolidated interest expense for the four most recently ended fiscal quarters prior to such date is equal to or greater than 2.0 to 1.0. Puget Energy's EBITDA to interest expense was 3.5 to 1.0 for the twelve months ended December 31, 2024. At December 31, 2024, the Company was in compliance with all applicable covenants, including those pertaining to the payment of dividends.

Utility Plant

Utility Plant	12 Months Ended
	Dec. 31, 2024
Utility Plant [Abstract]
Utility Plant	Utility Plant The following table presents electric, natural gas and common utility plant classified by account: Puget Energy Puget Sound Energy Utility Plant Estimated Useful Life 1 December 31, December 31, (Dollars in Thousands) (Years) 2024 2023 2024 2023 Distribution plant 7-65 $ 8,983,586 $ 8,298,893 $ 10,474,294 $ 9,804,018 Production plant 12-90 3,310,663 3,173,514 3,928,187 3,805,294 Transmission plant 44-75 1,908,891 1,595,566 2,015,060 1,701,878 General plant 5-75 805,960 717,017 826,918 738,996 Intangible plant (including capitalized software) 2 3-50 716,038 586,749 706,576 577,291 Plant acquisition adjustment N/A 242,827 242,826 282,792 282,792 Underground storage 25-60 50,047 46,761 63,004 60,171 Liquefied natural gas storage 25-50 256,144 224,337 257,909 226,208 Plant held for future use N/A 59,657 59,409 59,809 59,561 Recoverable cushion gas N/A 8,784 8,784 8,784 8,784 Plant not classified N/A 733,184 1,032,004 733,184 1,032,002 Finance leases, net of accumulated amortization 3 N/A 91,045 95,114 91,045 95,114 Less: accumulated provision for depreciation (5,101,926) (4,643,833) (7,382,662) (6,954,968) Subtotal $ 12,064,900 $ 11,437,141 $ 12,064,900 $ 11,437,141 Construction work in progress 1,577,695 1,156,265 1,577,695 1,156,265 Net utility plant $ 13,642,595 $ 12,593,406 $ 13,642,595 $ 12,593,406 _______________________ 1. Estimated Useful Life years have been approved in the 2022 GRC. 2. Intangible assets include capitalized software and franchise agreements with useful lives ranging between 3-10 years and 10-50 years, respectively. 3. At December 31, 2024, and 2023, accumulated amortization of finance leases at Puget Energy and PSE was $18.3 million and $13.2 million, respectively. Jointly owned generating plant service costs are included in utility plant service cost at the Company's ownership share. The Company provides financing for its ownership interest in the jointly owned utility plants. The following tables indicate the Company’s percentage ownership and the extent of the Company’s investment in jointly owned generating plants in service at December 31, 2024. These amounts are also included in the Utility Plant table above, with the exception of Puget Energy's portion of the Tacoma LNG facility, which is reported in the Puget Energy "Other property and investments" financial statement line item. The Company's share of fuel costs and operating expenses for plant in service are included in the corresponding accounts in the Consolidated Statements of Income. Puget Energy Jointly Owned Generating Plants Energy Source (Fuel) Company’s Ownership Share Plant in Service at Cost Construction Work in Progress Accumulated Depreciation Colstrip Units 3 & 4 Coal 25.00% $ 324,451 $ — $ (233,934) Frederickson 1 Natural Gas 49.85 68,006 — (32,767) Jackson Prairie Natural Gas 33.34 48,174 688 (14,196) Tacoma LNG Natural Gas various 497,290 3,545 (36,847) Puget Sound Energy Jointly Owned Generating Plants Energy Source (Fuel) Company’s Ownership Share Plant in Service at Cost Construction Work in Progress Accumulated Depreciation Colstrip Units 3 & 4 Coal 25.00% $ 581,467 $ — $ (490,950) Frederickson 1 Natural Gas 49.85 73,658 — (38,418) Jackson Prairie Natural Gas 33.34 63,004 688 (29,025) Tacoma LNG Natural Gas various 246,893 240 (17,916) PSE has a 50% ownership interest in Colstrip Units 1 and 2 and a 25% interest in each of Colstrip Units 3 and 4, which are coal-fired generating units located in Colstrip, Montana. PSE has accelerated the depreciation of Colstrip Units 3 and 4 to December 31, 2025 as part of the 2019 GRC. The 2017 GRC repurposed PTCs and hydro-related treasury grants to recover unrecovered plant costs and to fund and recover decommissioning and remediation costs for Colstrip Units 1 through 4. Additional costs beyond those covered by PTCs and hydro-related treasury grants are being recovered through a separate Colstrip tariff as part of the 2022 GRC. In 2022, PSE and Talen Energy reached an agreement to transfer PSE's ownership interest in Colstrip Units 3 and 4 to Talen Energy on December 31, 2025. However, Talen emerged from a Chapter 11 bankruptcy in May 2023 without approval of the 2022 transfer agreement, which the parties agree makes the transfer agreement unenforceable. Given that the transfer contemplated by that agreement will not proceed, PSE entered into an agreement with NorthWestern Energy on July 30, 2024 to transfer PSE's ownership interest in Colstrip Units 3 and 4 to NorthWestern Energy on December 31, 2025. Management evaluated the agreement with Northwestern Energy and determined that abandonment accounting criteria was met as of December 31, 2024. Thus, PSE will apply abandonment accounting on the transfer date of December 31, 2025, until that date Colstrip Units 3 and 4 are classified as Electric Utility Plant on the Company's balance sheet as of December 31, 2024. Asset Retirement Obligation The Company has recorded liabilities for steam generation sites, combustion turbine generation sites, wind generation sites, distribution and transmission poles, natural gas mains, liquefied natural gas storage sites, and leased facilities where disposal is governed by ASC 410-20 “Asset Retirement and Environmental Obligations". The Company records its ARO liabilities for its electric transmission and distribution poles as well as gas distribution mains aligned with its underlying asset data with future estimates of retirements. For the twelve months ended December 31, 2024, the Company reviewed the estimated remediation costs related to the Beaver Creek Wind Project and determined that $18.8 million was warranted for the ARO liability. No ARO liability was warranted as of December 31, 2023. For the twelve months ended December 31, 2024, the Company reviewed the estimated remediation costs at Colstrip and determined $7.9 million was warranted for the Colstrip ARO liability for Colstrip Units 1-4, compared to no change for the 12 months ended December 31, 2023. For the twelve months ended December 31, 2024 and 2023, the Company recorded relief of ARO and environmental remediation liability of $6.0 million and $6.0 million, respectively. In addition, the Company recorded Tacoma LNG facility ARO liability of $4.2 million and $4.1 million for PSE and $4.1 million and $4.0 million for Puget LNG held only at Puget Energy as of December 31, 2024 and December 31, 2023, respectively. Puget Energy and Puget Sound Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 ARO beginning balance $ 207,034 $ 209,406 New ARO recognized in the period 18,811 — Relief of liability (6,049) (5,998) Revisions in estimated cash flows 9,471 (2,206) Accretion expense 6,676 5,832 ARO ending balance $ 235,943 $ 207,034 The Company has identified the following obligations, as defined by ASC 410, “ARO,” which were not recognized because the liability for these assets cannot be reasonably estimated at December 31, 2024: • A legal obligation under Federal Dangerous Waste Regulations to dispose of asbestos-containing material in facilities that are not scheduled for remodeling, demolition or sales. The disposal cost related to these facilities could not be measured since the retirement date is indeterminable; therefore, the liability cannot be reasonably estimated; • An obligation under Washington state law to decommission the wells at the Jackson Prairie natural gas storage facility upon termination of the project. Since the project is expected to continue as long as the Northwest pipeline continues to operate, the liability cannot be reasonably estimated; • An obligation to pay its share of decommissioning costs at the end of the functional life of the major transmission lines. The major transmission lines are expected to be used indefinitely; therefore, the liability cannot be reasonably estimated; • A legal obligation under Washington state environmental laws to remove and properly dispose of certain under and above ground fuel storage tanks. The disposal costs related to under and above ground storage tanks could not be measured since the retirement date is indeterminable; therefore, the liability cannot be reasonably estimated; • An obligation to pay decommissioning costs at the end of utility service franchise agreements to restore the surface of the franchise area. The decommissioning costs related to facilities at the franchise area could not be measured since the decommissioning date is indeterminable; therefore, the liability cannot be reasonably estimated; and • A potential legal obligation may arise upon the expiration of an existing FERC hydropower license if the FERC orders the project to be decommissioned, although PSE contends that the FERC does not have such authority. Given the value of ongoing generation, flood control and other benefits provided by these projects, PSE believes that the potential for decommissioning is remote and cannot be reasonably estimated. Beaver Creek Wind Project Beaver Creek is a utility-scale wind project located in Stillwater County, Montana, with an expected nameplate capacity of 248 MW that is expected to commence commercial operations in 2025. On September 15, 2023, PSE executed a membership interest purchase agreement with Caithness Beaver Creek, LLC for a 100% ownership interest in Caithness Montana Wind, LLC, which closed on December 1, 2023. Total consideration is expected to be $44.6 million of which $23.8 million has been paid as of December 31, 2024 and the remaining balance is expected to be paid in the first quarter of 2025. On December 1, 2023, PSE entered into a turbine supply agreement with GE Renewables North America, LLC to purchase 88 wind turbines. Total consideration is expected to be $266.9 million of which $234.6 million has been paid as of December 31, 2024 and the remaining balance is expected to be paid in the first quarter of 2025, as turbines are delivered and the project is completed. On January 26, 2024, PSE entered into a balance of plant agreement to complete the design and construction of the project. Total consideration is expected to be approximately $145.4 million. As of December 31, 2024, $506.5 million was recorded to construction work in progress in conjunction with the Beaver Creek wind project. Appaloosa Solar Project

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2024
Long-Term Debt, Unclassified [Abstract]
Long-term Debt	Long-Term Debt The following table presents outstanding long-term debt due dates and principal amounts, net of debt discount, issuance and other costs and fair value adjustments at December 31, 2024 and 2023: (Dollars in Thousands) December 31, Series Type Due 2024 2023 Puget Sound Energy: 7.150% First Mortgage Bond 2025 $ — $ 15,000 7.200% First Mortgage Bond 2025 — 2,000 7.020% Senior Secured Note 2027 300,000 300,000 7.000% Senior Secured Note 2029 100,000 100,000 3.900% Pollution Control Bond 2031 138,460 138,460 4.000% Pollution Control Bond 2031 23,400 23,400 5.330% Senior Secured Note 2034 400,000 — 5.483% Senior Secured Note 2035 250,000 250,000 6.724% Senior Secured Note 2036 250,000 250,000 6.274% Senior Secured Note 2037 300,000 300,000 5.757% Senior Secured Note 2039 350,000 350,000 5.795% Senior Secured Note 2040 325,000 325,000 5.764% Senior Secured Note 2040 250,000 250,000 4.434% Senior Secured Note 2041 250,000 250,000 5.638% Senior Secured Note 2041 300,000 300,000 4.300% Senior Secured Note 2045 425,000 425,000 4.223% Senior Secured Note 2048 600,000 600,000 3.250% Senior Secured Note 2049 450,000 450,000 2.893% Senior Secured Note 2051 450,000 450,000 4.700% Senior Secured Note 2051 45,000 45,000 5.448% Senior Secured Note 2053 400,000 400,000 5.685% Senior Secured Note 2054 400,000 — * Debt discount, issuance cost and other * (45,835) (39,813) Total PSE long-term debt $ 5,961,025 $ 5,184,047 Puget Energy: * Fair value adjustment of PSE long-term debt * $ (131,326) $ (139,834) 3.650% Senior Secured Note 2025 — 400,000 2.379% Senior Secured Note 2028 500,000 500,000 4.100% Senior Secured Note 2030 650,000 650,000 4.224% Senior Secured Note 2032 450,000 450,000 * Debt discount, issuance cost and other * (5,780) (7,571) Total Puget Energy long-term debt $ 7,423,919 $ 7,036,642 ___________________ * Not Applicable. PSE's senior secured notes will cease to be secured by the pledged first mortgage bonds on the date (the "Substitution Date") that all of the first mortgage bonds issued and outstanding under the electric or natural gas utility mortgage indenture have been retired. As of December 31, 2024, the latest maturity date of the first mortgage bonds, other than pledged first mortgage bonds, is December 22, 2025. On the Substitution Date, PSE will deliver to the trustee for PSE's senior secured notes substitute pledged first mortgage bonds to be issued under a new mortgage indenture. As a result, as of the Substitution Date PSE's outstanding senior secured notes and any future series of PSE's senior secured notes will be secured by substitute pledged first mortgage bonds. Puget Energy Long-Term Debt In March 2022, Puget Energy filed an S-3 shelf registration statement under which it may issue up to $1.0 billion aggregate principal amount of senior notes secured by Puget Energy's assets. As of the date of this report, $550.0 million was available to be issued. The shelf registration will expire in March 2025. Puget Sound Energy Long-Term Debt In August 2022, PSE filed an S-3 shelf registration statement under which it may issue up to $1.4 billion aggregate principal amount of senior notes secured by first mortgage bonds. As of the date of this report, $200.0 million was available to be issued. The shelf registration will expire in August 2025. On June 11, 2024, PSE issued $400.0 million of senior secured notes at an interest rate of 5.330%. The notes mature on June 15, 2034 and pay interest semi-annually in arrears on June 15 and December 15 of each year, commencing on December 15, 2024. Proceeds from the issuance of the notes were invested in short-term money market funds, used to pay down outstanding commercial paper and for general corporate purposes. On June 11, 2024, PSE issued $400.00 million of green senior secured notes at an interest rate of 5.685%. The notes mature on June 15, 2054 and pay interest semi-annually in arrears on June 15 and December 15 of each year, commencing on December 15, 2024. Net proceeds from the issuance of the notes were invested in short-term money market funds and are intended to be used for allocation to eligible projects, as defined in PSE’s sustainable financing framework, which was published in May 2023. Eligible Projects are expenditures incurred and investments made related to development and acquisition of some or all of the following types of projects: (i) renewable energy, (ii) energy efficiency, (iii) clean transportation, (iv) biodiversity conservation, (v) climate change adaptation, (vi) water and wastewater management, (vii) pollution prevention and control, and (viii) green innovation. On May 18, 2023, PSE issued $400.0 million of green senior secured notes at an interest rate of 5.448%. The notes mature on June 1, 2053 and pay interest semi-annually in arrears on June 1 and December 1 of each year, commencing December 1, 2023. Net proceeds from the issuance of the notes were deposited into the Company's general account and are intended to be used for allocation to eligible projects, as defined in PSE's sustainable financing framework, which was published in May 2023. Eligible projects are expenditures incurred and investments made related to development and acquisition of some or all of the following types of projects: (i) renewable energy, (ii) energy efficiency, (iii) clean transportation, (iv) biodiversity conservation, (v) climate change adaptation, (vi) water and wastewater management, (vii) pollution prevention and control, and (viii) green innovation. Long-Term Debt Maturities The principal amounts of long-term debt maturities for the next five years and thereafter are as follows: (Dollars in Thousands) 2025 2026 2027 2028 2029 Thereafter Total Maturities of: PSE $ 17,000 $ — $ 300,000 $ — $ 100,000 $ 5,606,860 $ 6,023,860 Puget Energy 400,000 — — 500,000 — 1,100,000 2,000,000 Total long-term debt $ 417,000 $ — $ 300,000 $ 500,000 $ 100,000 $ 6,706,860 $ 8,023,860

Liquidity Facilities and Other

Liquidity Facilities and Other Financing Arrangements	12 Months Ended
	Dec. 31, 2024
Liquidity Facilities and Other Financing Arrangements [Abstract]
Liquidity Facilities and Other Financing Arrangements	Liquidity Facilities and Other Financing Arrangements As of December 31, 2024 and 2023, PSE had $40.0 million and $336.6 million in short-term debt outstanding, respectively. Outside of the consolidation of PSE’s short-term debt, Puget Energy had $338.4 million and $261.5 million, in short-term debt, drawn and outstanding under its credit facility as of December 31, 2024 and 2023, respectively. PSE’s weighted-average interest rate on short-term debt, including borrowing rate, commitment fees and the amortization of debt issuance costs, during 2024 and 2023 was 8.5% and 9.0%, respectively. As of December 31, 2024, PSE and Puget Energy had several committed credit facilities that are described below. Puget Sound Energy Credit Facility In May 2022, PSE entered into a new $800.0 million credit facility to replace the existing facility. The terms and conditions, including fees, financial covenant, expansion feature and credit spreads remain substantially the same. The base interest rate on loans has changed to the Secured Overnight Financing Rate (SOFR), as the LIBOR was discontinued on June 30, 2023. The proceeds of the PSE credit facility are to be used for general corporate purposes. The maturity date of the credit facility is May 14, 2027. The credit facility includes a swingline feature allowing same day availability on borrowings up to $75.0 million and has an expansion feature which, upon receipt of commitments from one or more lenders, could increase the total size of the facility up to $1.4 billion. The credit agreement is syndicated among numerous lenders and contains usual and customary affirmative and negative covenants that, among other things, place limitations on PSE's ability to transact with affiliates, make asset dispositions and investments or permit liens to exist. The credit agreement also contains a leverage ratio that requires the ratio of (a) total funded indebtedness to (b) total capitalization to be 65.0% or less at all times. PSE certifies its compliance with such covenants to participating banks each quarter. As of December 31, 2024, PSE was in compliance with all applicable covenant ratios. The credit agreement allows PSE to borrow at a prime based rate or to make floating rate advances at the SOFR, in either case, plus a spread that is based upon PSE's credit rating. PSE must pay a commitment fee on the unused portion of the credit facility. The spreads and the commitment fee depend on PSE's credit ratings. As of the date of this report, interest was calculated as SOFR plus 0.10% SOFR adjustment plus 1.25% spread over the adjusted SOFR rate and the commitment fee was 0.175%. As of December 31, 2024, no amount was drawn under PSE's credit facility and $40.0 million was outstanding under the commercial paper program. Outside of the credit facility, PSE maintains a standby letter of credit with TD Bank allowing for standby letter of credit postings of up to $150.0 million as a condition of transacting on the ICE NGX platform as well as participating in the Washington state carbon allowance auctions. As of December 31, 2024, $6.6 million was issued under a standby letter of credit with TD Bank in support of natural gas and carbon allowance purchases. Additionally, PSE had a $1.9 million letter of credit in support of a long-term transmission contract. In support of purchase power contracts, PSE posted cash collateral of $15.0 million and maintained two standby letters of credit in the amounts of $60.0 million and $13.5 million. Demand Promissory Note On May 19, 2023, PSE amended and restated its revolving credit facility with Puget Energy, in the form of a credit agreement and a demand promissory note (Note) pursuant to which PSE may borrow up to $200.0 million from Puget Energy subject to approval by Puget Energy. Under the terms of the Note, PSE pays interest based on Puget Energy’s credit facility interest rate, which is SOFR plus 0.10% SOFR adjustment, plus 1.75% spread over the adjusted SOFR rate. As of December 31, 2024, there was no outstanding balance under the promissory note. Puget Energy Credit Facility In May 2022, Puget Energy entered into a new $800.0 million credit facility to replace the existing facility. The terms and conditions, including fees, financial covenant, expansion feature and credit spreads remain substantially the same. The base interest rate on loans has changed to the SOFR, as the LIBOR was discontinued on June 30, 2023. The proceeds of the Puget Energy credit facility are to be used for general corporate purposes. The maturity date of the credit facility is May 14, 2027. The Puget Energy revolving senior secured credit facility also has an accordion feature, upon receipt of commitments from one or more lenders, could increase the size of the facility up to $1.3 billion. The revolving senior secured credit facility provides Puget Energy the ability to borrow based on a prime based rate or SOFR, in either case, plus a spread based on Puget Energy's credit ratings. Puget Energy must pay a commitment fee on the unused portion of the facility. As of the date of this report, interest was calculated as SOFR plus 0.10% SOFR adjustment plus 1.75% spread over the adjusted SOFR rate and the commitment fee was 0.275%. The revolving senior secured credit facility contains usual and customary affirmative and negative covenants. The credit agreement also contains a leverage ratio that requires the ratio of (a) total funded indebtedness to (b) total capitalization to be 65.0% or less at all times. As of December 31, 2024, Puget Energy was in compliance with all applicable covenants. On August 31, 2023, Puget Energy borrowed $100.0 million on its credit facility and contributed the proceeds to PSE as an equity contribution. The equity proceeds were used for general corporate purposes. On June 17, 2024, Puget Equico LLC, Puget Energy's parent company, contributed $292.8 million as an equity contribution to Puget Energy. Puget Energy then contributed $292.8 million to PSE as an equity contribution. The proceeds from the equity contribution were used for general corporate purposes.

Leases

Leases	12 Months Ended
	Dec. 31, 2024
Leases [Abstract]
Lessee, Operating and Finance Leases	Leases PSE has operating leases for buildings for corporate offices and operations, real estate for operating facilities and the PSE and Puget LNG facility, land for our wind farms and vehicles for PSE’s fleet. Finance leases represent office printers and office buildings. The leases have remaining lease terms of less than a year to 45 years. PSE's right-of-use (ROU) assets and lease liabilities include options to extend leases when it is reasonably certain that PSE will exercise that option. The components of lease cost were as follows: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Finance lease cost: Amortization of right-of-use asset $ 3,915 $ 3,891 Interest on lease liabilities 3,192 3,237 Total finance lease cost $ 7,107 $ 7,128 Operating lease cost 1 $ 24,993 $ 23,891 _______________ 1. Includes $1.7 million and $1.7 million allocated to Puget LNG at Puget Energy related to the Port of Tacoma lease for the years ended December 31, 2024 and December 31, 2023, respectively. Supplemental cash flow information related to leases was as follows: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flow for operating leases $ 17,038 $ 15,990 Investing cash flow for operating leases 1 7,955 7,901 Operating cash flow for finance leases 3,192 3,237 Financing cash flow for finance leases 3,915 3,891 Non-cash disclosure upon commencement of new lease Right-of-use assets obtained in exchange for new operating lease liabilities $ 4,093 $ 10,462 Right-of-use assets obtained in exchange for new finance lease liabilities 1,832 1,245 Non-cash disclosure upon modification of existing lease Modification of operating lease right-of-use assets $ 1,996 $ 6,912 _______________ 1 Includes $1.7 million and $1.7 million allocated to Puget LNG at Puget Energy related to the Port of Tacoma lease for the years ended December 31, 2024 and December 31, 2023, respectively. Supplemental balance sheet information related to leases was as follows: Puget Energy and (Dollars in Thousands) At December 31, Operating Leases 2024 2023 Operating lease right-of-use asset $ 181,397 $ 194,321 Operating leases liabilities current $ 22,761 $ 21,629 Operating lease liabilities long-term 166,700 180,754 Total operating lease liabilities: $ 189,461 $ 202,383 Finance Leases Common plant $ 53,594 $ 55,756 Natural gas plant 310 — Electric plant 37,141 39,358 Total finance lease assets $ 91,045 $ 95,114 Other current liabilities $ 3,786 $ 3,371 Finance lease liabilities 96,850 99,512 Total finance lease liabilities $ 100,636 $ 102,883 Weighted Average Remaining Lease Term Operating leases 21.2 Years 21.3 Years Finance leases 16.9 Years 18.0 Years Weighted Average Discount Rate Operating leases 3.76 % 3.75 % Finance leases 3.10 % 3.08 % The following table summarizes the Company’s estimated future minimum lease payments as of December 31, 2024: Puget Energy and Future Minimum Lease Payments (Dollars in Thousands) At December 31, Operating Leases Finance Leases 2025 $ 24,687 $ 7,097 2026 24,858 7,140 2027 24,469 7,023 2028 21,680 7,106 2029 12,622 6,964 Thereafter 153,937 96,138 Total lease payments $ 262,253 $ 131,468 Less imputed interest (72,792) (30,832) Total net present value $ 189,461 $ 100,636 Leases Not Yet Commenced On September 20, 2023, PSE entered into a tolling agreement to purchase the energy and capacity associated with a 132.5 MW natural gas combined cycle facility. The tolling agreement represents a lease to PSE and is expected to commence in October 2025. PSE expects the total lease payment consideration will approximate $91.0 million over the five year lease term beginning in October 2025. On December 12, 2023, PSE entered into a lease for an operations training facility located in Puyallup, Washington. The lease is expected to commence in 2025 and PSE expects the future the total lease payment consideration will approximate $116.0 million over the 20 year lease term. Construction of the facility will be managed and contracted by the lessor; however, PSE will have involvement in the design of the facility. On May 8, 2024, PSE entered into a battery storage tolling agreement that will be accounted for as a lease upon commencement. The lease is expected to commence in August 2027 and has a term of 20 years. The expected total lease payment consideration will approximate $744.0 million over the lease term. On May 23, 2024, PSE entered into a battery storage tolling agreement that will be accounted for as a lease upon commencement. The lease is expected to commence in September 2027 and has a term of 25 years. The expected total lease payment consideration will approximate $856.2 million over the lease term.

Accounting for Derivative Instr

Accounting for Derivative Instruments and Hedging Activities	12 Months Ended
	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Accounting for Derivative Instruments and Hedging Activities	Accounting for Derivative Instruments and Hedging Activities PSE employs various energy portfolio optimization strategies, but is not in the business of assuming risk for the purpose of realizing speculative trading revenue. The nature of serving regulated electric customers with its portfolio of owned and contracted electric generation resources exposes PSE and its customers to some volumetric and commodity price risks within the sharing mechanism of the PCA. Therefore, wholesale market transactions and PSE's related hedging strategies are focused on reducing costs and risks where feasible, thus reducing volatility in costs in the portfolio. In order to manage its exposure to the variability in future cash flows for forecasted energy transactions, PSE utilizes a programmatic hedging strategy which extends out three years. PSE's hedging strategy includes a risk-responsive component for the core natural gas portfolio, which utilizes quantitative risk-based measures with defined objectives to balance both portfolio risk and hedge costs. PSE's energy risk portfolio management function monitors and manages these risks using analytical models and tools. In order to manage risks effectively, PSE enters into forward physical electric and natural gas purchase and sale agreements, fixed-for-floating swap contracts, and commodity call/put options. Currently, the Company does not apply cash flow hedge accounting, and therefore records all mark-to-market gains or losses through earnings. The Company manages its interest rate risk through the issuance of mostly fixed-rate debt with varied maturities. The Company utilizes internal cash from operations, borrowings under its commercial paper program, and its credit facilities to meet short-term funding needs. The Company may enter into swap instruments or other financial hedge instruments to manage the interest rate risk associated with these debts. The following table presents the volumes, fair values and classification of the Company's derivative instruments recorded on the balance sheets: Puget Energy and Year Ended December 31, (Dollars in Thousands) Volumes (millions) Assets 1 Liabilities² 2024 2023 2024 2023 2024 2023 Electric portfolio derivatives 3 * * $ 35,341 $ 93,028 $ 319,506 $ 126,939 Natural gas derivatives (MMBtus) 3 269 301 3,495 16,521 70,425 96,898 Total derivative contracts $ 38,836 $ 109,549 $ 389,931 $ 223,837 Current $ 32,591 $ 74,225 $ 218,443 $ 185,788 Long-term 6,245 35,324 171,488 38,049 Total derivative contracts $ 38,836 $ 109,549 $ 389,931 $ 223,837 __________ 1. Balance sheet classification: Current and Long-term Unrealized gain on derivative instruments. 2. Balance sheet classification: Current and Long-term Unrealized loss on derivative instruments. 3. All fair value adjustments on derivatives have been deferred in accordance with ASC 980, “Regulated Operations" in 2024. The net derivative asset or liability and offsetting regulatory liability or asset are related to contracts used to economically hedge the cost of electricity and physical gas purchased to serve customers. In 2023, only fair value adjustments for contracts used to serve natural gas customers were deferred. * Electric portfolio derivatives consist of electric generation fuel of 283.5 million One Million British Thermal Units (MMBtus) and purchased electricity of 13.3 million megawatt hours (MWhs) at December 31, 2024, and 315.6 million MMBtus and 2.3 million MWhs at December 31, 2023. It is the Company's policy to record all derivative transactions on a gross basis at the contract level without offsetting assets or liabilities. The Company generally enters into transactions using the following master agreements: WSPP, Inc. (WSPP) agreements, which standardize physical power contracts; International Swaps and Derivatives Association (ISDA) agreements, which standardize financial natural gas and electric contracts; and North American Energy Standards Board (NAESB) agreements, which standardize physical natural gas contracts. The Company believes that such agreements reduce credit risk exposure because such agreements provide for the netting and offsetting of monthly payments as well as the right of set-off in the event of counterparty default. The set-off provision can be used as a final settlement of accounts which extinguishes the mutual debts owed between the parties in exchange for a new net amount. For further details regarding the fair value of derivative instruments, see Note 11, "Fair Value Measurements", to the consolidated financial statements included in Item 8 of this report. The following tables present the potential effect of netting arrangements, including rights of set-off associated with the Company's derivative assets and liabilities: Puget Energy and December 31, 2024 (Dollars in Thousands) Gross Amount Recognized in the Consolidated Balance Sheet 1 Gross Amounts Offset in the Consolidated Balance Sheet Net of Amounts Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Commodity Contracts 2 Cash Collateral Received/Pledged Net Amount Assets: Energy derivative contracts $ 38,836 $ — $ 38,836 $ (34,329) $ — $ 4,507 Liabilities: Energy derivative contracts $ 389,931 $ — $ 389,931 $ (34,329) $ (3,593) $ 352,009 Puget Energy and December 31, 2023 (Dollars in Thousands) Gross Amount Recognized 1 Gross Amounts Offset in the Consolidated Balance Sheet Net of Amounts Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Commodity Contracts 2 Cash Collateral Received/Pledged Net Amount Assets Energy derivative contracts $ 109,549 $ — $ 109,549 $ (82,206) $ — $ 27,343 Liabilities Energy derivative contracts $ 223,837 $ — $ 223,837 $ (82,206) $ (84) $ 141,547 __________ 1. All derivative contract deals are executed under ISDA, NAESB, and WSPP master agreements with right of set-off. 2. Amounts reflect netting by Counterparty and right of set-off. The following table presents the effect and locations of the realized and unrealized gains (losses) of the Company's derivatives recorded on the statements of income: Puget Energy and Year Ended December 31, (Dollars in Thousands) Location 2024 2023 2022 Gas for Power Derivatives: Unrealized Unrealized gain (loss) on derivative instruments, net $ 53,541 $ (155,774) $ 61,761 Realized Electric generation fuel (85,476) 47,930 158,550 Power Derivatives: Unrealized Unrealized gain (loss) on derivative instruments, net (19,630) (128,721) 199,416 Realized Purchased electricity (76,271) 69,136 20,917 Total gain (loss) recognized in income on derivatives $ (127,836) $ (167,429) $ 440,644 The Company is exposed to credit risk primarily through buying and selling electricity and natural gas to serve its customers. Credit risk is the potential loss resulting from a counterparty's non-performance under an agreement. The Company manages credit risk with policies and procedures for, among other things, counterparty credit analysis, exposure measurement, and exposure monitoring and mitigation. The Company monitors counterparties for significant swings in credit default swap rates, credit rating changes by external rating agencies, ownership changes or financial distress. Where deemed appropriate, the Company may request collateral or other security from its counterparties to mitigate potential credit default losses. Criteria employed in this decision include, among other things, the perceived creditworthiness of the counterparty and the expected credit exposure. It is possible that volatility in energy commodity prices could cause the Company to have material credit risk exposure with one or more counterparties. If such counterparties fail to perform their obligations under one or more agreements, the Company could suffer a material financial loss. However, as of December 31, 2024, approximately 99.8% of the Company's energy portfolio exposure, excluding normal purchase normal sale (NPNS) transactions, is with counterparties that are rated investment grade by rating agencies and 0.2% are either rated below investment grade or not rated by rating agencies. The Company assesses credit risk internally for counterparties that are not rated by the major rating agencies. The Company computes credit reserves at a master agreement level by counterparty. The Company considers external credit ratings and market factors in the determination of reserves, such as credit default swaps and bond spreads. The Company recognizes that external ratings may not always reflect how a market participant perceives a counterparty's risk of default. The Company uses both default factors published by Standard & Poor's and factors derived through analysis of market risk, which reflect the application of an industry standard recovery rate. The Company selects a default factor by counterparty at an aggregate master agreement level based on a weighted average default tenor for that counterparty's deals. The default tenor is determined by weighting the fair value and contract tenors for all deals for each counterparty to derive an average value. The default factor used is dependent upon whether the counterparty is in a net asset or a net liability position after applying the master agreement levels. The Company applies the counterparty's default factor to compute credit reserves for counterparties that are in a net asset position. The Company calculates a non-performance risk on its derivative liabilities by using its estimated incremental borrowing rate over the risk-free rate. Credit reserves are netted against unrealized gain (loss) positions. As of December 31, 2024, the Company was in a net liability position with the majority of counterparties, so the default factors of counterparties did not have a significant impact on reserves for the period. The majority of the Company's derivative contracts are with financial institutions and other utilities operating within the Western Electricity Coordinating Council. PSE also transacts power futures contracts on the ICE, and natural gas contracts on the ICE NGX exchange platform. Execution of contracts on ICE requires the daily posting of margin calls as collateral through a futures and clearing agent. As of December 31, 2024, PSE had cash posted as collateral of $7.8 million related to contracts executed on the ICE platform. As a condition of transacting on the ICE NGX platform as well as participating in the Washington state carbon allowance auctions, PSE maintains a standby letter of credit agreement with TD Bank. As of December 31, 2024, PSE had no cash posted with ICE NGX, and $6.6 million was issued under the standby letter of credit agreement in support of natural gas and carbon allowance purchases. PSE did not trigger any collateral requirements with any of its counterparties nor were any of PSE's counterparties required to post collateral resulting from credit rating downgrades during the twelve months ended December 31, 2024. The following table presents the aggregate fair value of all derivative instruments with credit-risk-related contingent features that are in a liability position and the amount of additional collateral the Company could be required to post: Puget Energy and December 31, (Dollars in Thousands) 2024 2023 Contingent Feature Fair Value 1 Liability Posted Contingent Fair Value 1 Liability Posted Contingent Credit rating 2 $ 179,532 $ — $ 179,532 $ 13,384 $ — $ 13,384 Requested credit for adequate assurance 37,492 — — 53,427 — — Forward value of contract 3 19,905 12,915 N/A 84 12,429 N/A Total $ 236,929 $ 12,915 $ 179,532 $ 66,895 $ 12,429 $ 13,384 _______________ 1. Represents the derivative fair value of contracts with contingent features for counterparties in net derivative liability positions. Excludes NPNS, accounts payable and accounts receivable. 2. Failure by PSE to maintain an investment grade credit rating from each of the major credit rating agencies provides counterparties a contractual right to demand collateral. 3. Collateral requirements may vary, based on changes in the forward value of underlying transactions relative to contractually defined collateral thresholds.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2024
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements ASC 820 established a fair value hierarchy that prioritizes the inputs used to measure fair value. The hierarchy categorizes the inputs into three levels with the highest priority given to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurement) and the lowest priority given to unobservable inputs (Level 3 measurement). The three levels of the fair value hierarchy are as follows: Level 1 - Quoted prices are available in active markets for identical assets or liabilities as of the reporting date. Level 1 primarily consists of financial instruments such as exchange-traded derivatives and listed equities. Equity securities that are also classified as cash equivalents are considered Level 1 if there are unadjusted quoted prices in active markets for identical assets or liabilities. Level 2 - Pricing inputs are other than quoted prices in active markets included in Level 1, which are either directly or indirectly observable as of the reporting date. Level 2 includes those financial instruments that are valued using models or other valuation methodologies. Instruments in this category include non-exchange-traded derivatives such as over-the-counter forwards and options. Level 3 - Pricing inputs include significant inputs that have little or no observability as of the reporting date. These inputs may be used with internally developed methodologies that result in management's best estimate of fair value. Financial assets and liabilities measured at fair value are classified in their entirety in the appropriate fair value hierarchy based on the lowest level of input that is significant to the fair value measurement. The Company's assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of fair value assets and liabilities and their placement within the fair value hierarchy. The Company primarily determines fair value measurements classified as Level 2 or Level 3 using a combination of the income and market valuation approaches. The process of determining the fair values is the responsibility of the derivative accounting department which reports to the Controller and Principal Accounting Officer. Inputs used to estimate the fair value of forwards, swaps and options include market-price curves, contract terms and prices, credit-risk adjustments, and discount factors. Additionally, for options, the Black-Scholes option valuation model and implied market volatility curves are used. Inputs used to estimate fair value in industry-standard models are categorized as Level 2 inputs as substantially all assumptions and inputs are observable in active markets throughout the full term of the instruments. On a daily basis, the Company obtains quoted forward prices for the electric and natural gas markets from an independent external pricing service. The Company considers its electric and natural gas contracts as Level 2 derivative instruments as such contracts are commonly traded as over-the-counter forwards with indirectly observable price quotes. However, certain energy derivative instruments with maturity dates falling outside the range of observable price quotes or that are transacted at illiquid delivery locations are classified as Level 3 in the fair value hierarchy. Management's assessment is based on the trading activity in real-time and forward electric and natural gas markets. Each quarter, the Company confirms the validity of pricing-service quoted prices used to value Level 2 commodity contracts with the actual prices of commodity contracts entered into during the most recent quarter. Assets and Liabilities with Estimated Fair Value The carrying values of cash and cash equivalents, restricted cash, and short-term debt as reported on the balance sheet are reasonable estimates of their fair value due to the short-term nature of these instruments and are classified as Level 1 in the fair value hierarchy. The carrying value of other investments of $45.4 million and $44.6 million at December 31, 2024, and 2023, respectively, are included in "Other property and investments" on the balance sheet. These values are also reasonable estimates of their fair value and classified as Level 2 in the fair value hierarchy as they are valued based on market rates for similar transactions. The fair value of long-term notes were estimated using the discounted cash flow method with U.S. Treasury yields and Company's credit spreads as inputs, interpolating to the maturity date of each issue. The carrying values and estimated fair values were as follows: Puget Energy December 31, 2024 December 31, 2023 (Dollars in Thousands) Level Carrying Value Fair Value Carrying Value Fair Value Financial liabilities: Long-term debt (fixed-rate), net of discount 1 2 $ 7,423,919 $ 6,966,211 $ 7,036,642 $ 6,855,503 Total $ 7,423,919 $ 6,966,211 $ 7,036,642 $ 6,855,503 Puget Sound Energy December 31, 2024 December 31, 2023 (Dollars in Thousands) Level Carrying Value Fair Value Carrying Value Fair Value Financial liabilities: Long-term debt (fixed-rate), net of discount 2 2 $ 5,961,025 $ 5,492,999 $ 5,184,047 $ 5,007,483 Total $ 5,961,025 $ 5,492,999 $ 5,184,047 $ 5,007,483 _______________ 1. The carrying value includes debt issuances costs of $21.3 million and $21.0 million for December 31, 2024, and 2023, respectively, which are not included in fair value. 2. The carrying value includes debt issuances costs of $22.1 million and $21.2 million for December 31, 2024, and 2023, respectively, which are not included in fair value. Assets and Liabilities Measured at Fair Value on a Recurring Basis The following tables present the Company's financial assets and liabilities by level, within the fair value hierarchy, that were accounted for at fair value on a recurring basis and the reconciliation of the changes in the fair value of Level 3 derivatives in the fair value hierarchy: Puget Energy and Fair Value Fair Value December 31, 2024 December 31, 2023 (Dollars in Thousands) Level 2 Level 3 Total Level 2 Level 3 Total Assets: Electric derivative instruments $ 25,236 $ 10,105 $ 35,341 $ 42,254 $ 50,774 $ 93,028 Gas derivative instruments 1,729 1,766 3,495 11,647 4,874 16,521 Total derivative assets $ 26,965 $ 11,871 $ 38,836 $ 53,901 $ 55,648 $ 109,549 Liabilities: Electric derivative instruments $ 134,292 $ 185,214 $ 319,506 $ 103,427 $ 23,512 $ 126,939 Gas derivative instruments 70,050 375 70,425 95,875 1,023 96,898 Compliance obligation 73,049 — 73,049 168,879 — 168,879 Total derivative liabilities $ 277,391 $ 185,589 $ 462,980 $ 368,181 $ 24,535 $ 392,716 Puget Energy and Year Ended December 31, Level 3 Roll-Forward Net Asset (Liability) 2024 2023 2022 (Dollars in Thousands) Electric Natural Gas Total Electric Natural Gas Total Electric Natural Gas Total Balance at beginning of period $ 27,262 $ 3,851 $ 31,113 $ 116,078 $ (127) $ 115,951 $ (42,752) $ (2,120) $ (44,872) Changes during period: Realized and unrealized energy derivatives Included in earnings 1 (27,262) — (27,262) (56,656) — (56,656) 180,533 — 180,533 Included in regulatory assets / liabilities (211,129) 1,284 (209,845) — 4,906 4,906 — 301 301 Settlements 2 34,873 (4,418) 30,455 (32,377) (1,098) (33,475) (21,972) 1,369 (20,603) Transferred into Level 3 — — — — — — — — — Transferred out Level 3 1,146 674 1,820 217 170 387 269 323 592 Balance at end of period $ (175,110) $ 1,391 $ (173,719) $ 27,262 $ 3,851 $ 31,113 $ 116,078 $ (127) $ 115,951 __________________ 1. Income Statement classification: Unrealized gain (loss) on derivative instruments, net. Includes unrealized gains (losses) on derivatives still held in position as of the reporting date for electric derivatives of $(17.3) million and $147.1 million for the years ended December 31, 2023, and 2022, respectively. 2. The Company had no purchases or sales of options during the reported periods. Realized gains and losses on energy derivatives for Level 3 recurring items are included in energy costs in the Company's consolidated statements of income under purchased electricity, electric generation fuel or purchased natural gas when settled. In order to determine which assets and liabilities are classified as Level 3, the Company receives market data from its independent external pricing service defining the tenor of observable market quotes. To the extent any of the Company's commodity contracts extend beyond what is considered observable as defined by its independent pricing service, the contracts are classified as Level 3. The actual tenor of what the independent pricing service defines as observable is subject to change depending on market conditions. Therefore, as the market changes, the same contract may be designated Level 3 one month and Level 2 the next, and vice versa. The changes of fair value classification into or out of Level 3 are recognized each month and reported in the Level 3 Roll-forward table above. The Company did not have any transfers between Level 2 and Level 1 during the years ended December 31, 2024, 2023, and 2022. The Company does transact at locations, or market price points, that are illiquid or for which no prices are available from the independent pricing service. In such circumstances the Company uses a more liquid price point and adjusts the price for transportation costs to the illiquid locations to serve as a proxy for market prices. Such transactions are classified as Level 3. The Company does not use internally developed models to make adjustments to significant unobservable pricing inputs. The only significant unobservable input into the fair value measurement of the Company's Level 3 assets and liabilities is the forward price for electric and natural gas contracts. Below are the forward price ranges for the Company's commodity contracts, as of December 31, 2024: Puget Energy and Fair Value Range (Dollars in Thousands) Assets 1 Liabilities 1 Valuation Technique Unobservable Input Low High Weighted Electricity $ 10,104 $ 185,214 Discounted cash flow Power Prices (per MWh) $ 13.82 $ 138.94 $ 64.59 Natural Gas $ 1,767 $ 376 Discounted cash flow Natural Gas Prices (per MMBtu) $ 2.66 $ 4.17 $ 3.66 _______________ 1 The valuation techniques, unobservable inputs and ranges are the same for asset and liability positions. The significant unobservable inputs listed above would have a direct impact on the fair values of the above instruments if they were adjusted. Consequently, significant increases or decreases in the forward prices of electricity or natural gas in isolation would result in a significantly higher or lower fair value for Level 3 assets and liabilities. Generally, interrelationships exist between market prices of natural gas and power. As such, an increase in natural gas pricing would potentially have a similar impact on forward power markets. At December 31, 2024, a hypothetical 10% increase or decrease in market prices of natural gas and electricity would change the fair value of the Company's derivative portfolio, classified as Level 3 within the fair value hierarchy, by $57.8 million. Long-Lived Assets Measured at Fair Value on a Nonrecurring Basis Puget Energy records the fair value of its intangible assets in accordance with ASC 360, “Property, Plant, and Equipment,” (ASC 360). The fair value assigned to the power contracts was determined using an income approach comparing the contract rate to the market rate for power over the remaining period of the contracts incorporating non-performance risk. Management also incorporated certain assumptions related to quantities and market presentation that it believes market participants would make in the valuation. The fair value of the power contracts is amortized as the contracts settle. ASC 360 requires long-lived assets to be tested for recoverability whenever events or changes in circumstances indicate that its carrying amount may not be recoverable. One such triggering event is a significant decrease in the forward market prices of power. Puget Energy evaluated the triggering event criteria in ASC 360 during 2024, 2023 and 2022 and determined there was no indication of impairment of its power purchase contracts.

Employee Investment Plans

Employee Investment Plans	12 Months Ended
	Dec. 31, 2024
Employee Investment Plans [Abstract]
Employee Investment Plans	Employee Investment Plans The Company's Investment Plan is a qualified employee 401(k) plan, under which employee salary deferrals and after-tax contributions are used to purchase several different investment fund options. PSE’s contributions to the employee Investment Plan were $31.7 million, $28.9 million and $25.2 million for the years 2024, 2023, and 2022, respectively. The employee Investment Plan eligibility requirements are set forth in the plan documents. Non-represented employees and United Association of Journeymen and Apprentices of the Plumbing and Pipefitting Industry (UA) represented employees hired before January 1, 2014, and International Brotherhood of Electrical Workers Local Union 77 (IBEW) represented employees hired before December 12, 2014, have the following company contributions: 1. For employees under the Cash Balance retirement plan formula, PSE will match 100% of an employee's contribution up to 6.0% of plan compensation each paycheck, and will make an additional year-end contribution equal to 1.0% of base pay. 2. For employees grandfathered under the Final Average Earning retirement plan formula, PSE will match 55.0% of an employee’s contribution up to 6.0% of plan compensation each paycheck. Non-represented and UA-represented employees hired on or after January 1, 2014 along with IBEW-represented employees hired on or after December 12, 2014, will have access to the 401(k) plan. The two contribution sources from PSE are below: 1. 401(k) Company Matching: For non-represented, UA-represented and IBEW-represented employees PSE will match: 100% match on the first 3.0% of pay contributed and 50.0% match on the next 3.0% of pay contributed, such that an employee who contributes 6.0% of pay will receive 4.5% of pay in company match. Company matching will be immediately vested. 2. Company Contribution: UA-represented employees will receive an annual company contribution of 4.0% of eligible pay placed in the Cash Balance retirement plan. Non-represented and IBEW-represented employees will receive an annual company contribution of 4.0% of eligible pay, placed either in the Investment Plan 401(k) plan or in PSE’s Cash Balance retirement plan. Non-represented and IBEW-represented employees will make a one-time election within 30 days of hire and direct that PSE put the 4.0% contribution either into the 401(k) plan or into an account in the Cash Balance retirement plan. The Company's 4.0% contribution will vest after three years of service.

Retirement Benefits

Retirement Benefits	12 Months Ended
	Dec. 31, 2024
Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Retirement Benefits	Retirement Benefits PSE has a defined benefit pension plan (Qualified Pension Benefits) covering a substantial majority of PSE employees. For employees hired prior to 2014, pension benefits earned are a function of age, salary, years of service and, in the case of employees in the cash balance formula plan, the applicable annual interest crediting rates. Effective January 1, 2014, all new UA represented employees hired or rehired receive annual pay credits of 4.0% of eligible pay each year in the cash balance formula of the defined pension plan. Effective January 1, 2014 for non-represented employees, and December 12, 2014 for employees represented by the IBEW, newly hired or rehired employees receive annual employer contributions of 4.0% of eligible pay each year into the cash balance formula of the defined benefit pension or 401k plan account. PSE also has a non-qualified Supplemental Executive Retirement Plan (SERP) for certain key senior management employees that closed to new participants in 2019. Effective 2019, PSE has an officer restoration benefit for new officers who join PSE or are promoted, such that company contributions under PSE’s applicable tax-qualified plan, which otherwise would have been credited if not for IRS limitations, are credited at 4.0% of earnings to an account with the Deferred Compensation Plan. In addition to providing pension benefits, PSE provides legacy group health care and life insurance benefits (Other Benefits) for certain retired employees. The group health care benefit is provided via a Retiree Health Reimbursement Account (HRA) Plan effective January 1, 2020. The life insurance benefits are provided principally through an insurance company. Puget Energy's retirement plans were remeasured as a result of the merger in 2009, which represents the difference between Puget Energy and PSE's retirement plans. The components of service cost are included within utility operations and maintenance for PSE and within non-utility expense and other for Puget Energy while all non-service cost components are included in other income. The following tables summarize the Company’s change in benefit obligation, change in plan assets and amounts recognized in the Statements of Financial Position for the years ended December 31, 2024, and 2023: Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Change in benefit obligation: Benefit obligation at beginning of period $ 609,103 $ 589,278 $ 26,824 $ 32,046 $ 8,597 $ 9,015 Amendments — — — — 34 78 Service cost 18,616 18,530 — 143 197 184 Interest cost 31,152 32,375 1,370 1,589 406 439 Curtailment loss / (gain) — — — (2,772) — — Actuarial loss (gain) (38,952) 8,469 (1,752) (661) (194) (52) Benefits paid (41,583) (38,258) (1,978) (3,521) (792) (1,067) Administrative expense (1,350) (1,291) — — — — Benefit obligation at end of period* $ 576,986 $ 609,103 $ 24,464 $ 26,824 $ 8,248 $ 8,597 • The amount is the actuarial present value of the vested benefits to which the employee is currently entitled and is based on the employee's expected date of separation or retirement. Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Change in plan assets: Fair value of plan assets at beginning of period $ 746,011 $ 658,533 $ — $ — $ 5,085 $ 5,190 Actual return on plan assets 51,509 109,028 — — 313 543 Employer contribution 18,000 18,000 1,978 3,521 179 419 Benefits paid (41,583) (38,258) (1,978) (3,521) (792) (1,067) Administrative expense (1,247) (1,292) — — — — Fair value of plan assets at end of period $ 772,690 $ 746,011 $ — $ — $ 4,785 $ 5,085 Funded status at end of period $ 195,704 $ 136,908 $ (24,464) $ (26,824) $ (3,463) $ (3,512) Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Amounts recognized in Consolidated Balance Sheet consist of: Noncurrent assets $ 195,704 $ 136,908 $ — $ — $ — $ — Current liabilities — — (6,759) (1,978) (237) (225) Noncurrent liabilities — — (17,705) (24,846) (3,226) (3,287) Net assets (liabilities) $ 195,704 $ 136,908 $ (24,464) $ (26,824) $ (3,463) $ (3,512) Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Change in plan obligation and plan asset: Projected benefit obligation $ 576,986 $ 609,103 $ 24,464 $ 26,824 $ 8,248 $ 8,597 Accumulated benefit obligation 571,306 601,981 24,464 26,824 8,109 8,487 Fair value of plan assets 772,690 746,011 — — 4,785 5,085 The following tables summarize Puget Energy's and PSE's pension benefit amounts recognized in accumulated other comprehensive income (AOCI) for the years ended December 31, 2024, and 2023: Puget Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Amounts recognized in Accumulated Other Comprehensive Income consist of: Net loss (gain) $ (49,242) $ (16,257) $ (3,579) $ (1,870) $ (2,132) $ (2,052) Prior service cost (credit) — — — — 311 310 Total $ (49,242) $ (16,257) $ (3,579) $ (1,870) $ (1,821) $ (1,742) Puget Sound Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Amounts recognized in Accumulated Other Comprehensive Income consist of: Net loss (gain) $ 39,183 $ 74,851 $ (3,342) $ (1,613) $ (2,204) $ (2,124) Prior service cost (credit) — — — — 311 310 Total $ 39,183 $ 74,851 $ (3,342) $ (1,613) $ (1,893) $ (1,814) The following tables summarize Puget Energy's and PSE's net periodic benefit cost for the years ended December 31, 2024, 2023, and 2022. Puget Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2022 2024 2023 2022 2024 2023 2022 Components of net periodic benefit cost: Service cost $ 18,616 $ 18,530 $ 26,351 $ — $ 143 $ 557 $ 197 $ 184 $ 217 Interest cost 31,152 32,375 24,263 1,370 1,589 1,253 406 439 311 Expected return on plan assets (54,896) (50,641) (51,014) — — — (288) (297) (379) Amortization of prior service cost (credit) — — — — 144 289 33 28 22 Amortization of net loss (gain) (2,684) (2,447) 6,381 (42) — 2,471 (139) (210) (29) Net periodic benefit cost $ (7,812) $ (2,183) $ 5,981 $ 1,328 $ 1,876 $ 4,570 $ 209 $ 144 $ 142 Puget Sound Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2022 2024 2023 2022 2024 2023 2022 Components of net periodic benefit cost: Service cost $ 18,616 $ 18,530 $ 26,351 $ — $ 143 $ 557 $ 197 $ 184 $ 217 Interest cost 31,152 32,375 24,263 1,370 1,589 1,253 406 439 311 Expected return on plan assets (54,897) (50,641) (51,016) — — — (288) (297) (379) Amortization of prior service cost (credit) — — — — 144 289 33 28 22 Amortization of net loss (gain) — — 15,080 (22) 44 2,648 (139) (230) (35) Net periodic benefit cost $ (5,129) $ 264 $ 14,678 $ 1,348 $ 1,920 $ 4,747 $ 209 $ 124 $ 136 The following tables summarize Puget Energy's and PSE's benefit obligations recognized in other comprehensive income (OCI) for the years ended December 31, 2024, and 2023: Puget Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Other changes (pre-tax) in plan assets and benefit obligations recognized in other comprehensive income: Net loss (gain) $ (44,439) $ (49,917) $ (1,751) $ (3,433) $ (219) $ (298) Amortization of net (loss) gain 2,684 2,447 42 — 139 210 Settlements, mergers, sales, and closures — — — (145) — — Prior service cost (credit) — — — — 34 79 Amortization of prior service (cost) credit — — — (144) (33) (28) Total change in other comprehensive income for year $ (41,755) $ (47,470) $ (1,709) $ (3,722) $ (79) $ (37) Puget Sound Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Other changes (pre-tax) in plan assets and benefit obligations recognized in other comprehensive income: Net loss (gain) $ (44,438) $ (49,916) $ (1,751) $ (3,433) $ (219) $ (298) Amortization of net (loss) gain — — 22 (44) 139 230 Settlements, mergers, sales, and closures — — — (145) — — Prior service cost (credit) — — — — 34 79 Amortization of prior service (cost) credit — — — (144) (33) (28) Total change in other comprehensive income for year $ (44,438) $ (49,916) $ (1,729) $ (3,766) $ (79) $ (17) The aggregate expected contributions by the Company to fund the qualified pension plan, SERP and the other postretirement plans for the year ending December 31, 2025, are expected to be at least $18.0 million, $6.8 million and $0.2 million, respectively. Assumptions In accounting for pension and other benefit obligations and costs under the plans, the following weighted-average actuarial assumptions were used by the Company: Qualified SERP Other Benefit Obligation Assumptions: 2024 2023 2022 2024 2023 2022 2024 2023 2022 Discount rate 5.80 % 5.30 % 5.60 % 5.80 % 5.30 % 5.60 % 5.80 % 5.30 % 5.60 % Rate of compensation increase 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 Interest crediting rate 4.00 4.00 4.00 N/A N/A N/A N/A N/A N/A Benefit Cost Assumptions: Discount rate 5.30 5.60 3.00 5.30 5.60 3.00 5.30 5.60 3.00 Return on plan assets 7.00 6.75 6.50 — — — 7.00 7.00 7.00 Rate of compensation increase 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 Interest crediting rate 4.00 4.00 4.00 N/A N/A N/A N/A N/A N/A The Company has selected the expected return on plan assets based on a historical analysis of rates of return and the Company’s investment mix, market conditions, inflation and other factors. The expected rate of return is reviewed annually based on these factors. The Company’s accounting policy for calculating the market-related value of assets for the Company’s retirement plan is based on a five-year smoothing of asset gains (losses) measured from the expected return on market-related assets. This is a calculated value that recognizes changes in fair value in a systematic and rational manner over five years. The same manner of calculating market-related value is used for all classes of assets, and is applied consistently from year to year. Puget Energy’s pension and other postretirement benefits income or costs depend on several factors and assumptions, including plan design, timing and amount of cash contributions to the plan, earnings on plan assets, discount rate, expected long-term rate of return, and mortality trends. Changes in any of these factors or assumptions will affect the amount of income or expense that Puget Energy records in its financial statements in future years and its projected benefit obligation. Puget Energy has selected an expected return on plan assets based on a historical analysis of rates of return and Puget Energy’s investment mix, market conditions, inflation and other factors. As required by merger accounting rules, market-related value was reset to market value effective with the merger. The discount rates were determined by using market interest rate data and the weighted-average discount rate from the FTSE Pension Discount Curve (formerly known as the Citigroup Pension Liability Index Curve). The Company also takes into account in determining the discount rate the expected changes in market interest rates and anticipated changes in the duration of the plan liabilities. The Company's projected benefit obligation for pension plans experienced an actuarial gain of $39.0 million in 2024. This is primarily due to the change of census data, which increases the expected benefit obligation. Plan Benefits The expected total benefits to be paid during the next five years and the aggregate total to be paid for the five years thereafter are as follows: (Dollars in Thousands) 2025 2026 2027 2028 2029 2030-2034 Qualified Pension total benefits $ 43,800 $ 44,700 $ 45,400 $ 46,100 $ 47,100 $ 242,200 SERP Pension total benefits 6,759 2,263 4,222 1,630 1,559 7,295 Other Benefits total 870 847 838 834 837 3,491 Plan Assets Plan contributions and the actuarial present value of accumulated plan benefits are prepared based on certain assumptions pertaining to interest rates, inflation rates and employee demographics, all of which are subject to change. Due to uncertainties inherent in the estimations and assumptions process, changes in these estimates and assumptions in the near term may be material to the financial statements. The Company has a Retirement Plan Committee that establishes investment policies, objectives and strategies designed to balance expected return with a prudent level of risk. All changes to the investment policies are reviewed and approved by the Retirement Plan Committee prior to being implemented. The Retirement Plan Committee invests trust assets with investment managers who have historically achieved above-median long-term investment performance within the risk and asset allocation limits that have been established. Interim evaluations are routinely performed with the assistance of an outside investment consultant. To obtain the desired return needed to fund the pension benefit plans, the Retirement Plan Committee has established investment allocation percentages by asset classes as follows: Allocation Asset Class Minimum Target Maximum Domestic large cap equity 22 % 28 % 35 % Domestic small cap equity — 8 12 Non-U.S. equity 10 24 30 Fixed income 30 40 50 Cash — — 5 Plan Fair Value Measurements ASC 715, “Compensation – Retirement Benefits” (ASC 715) directs companies to provide additional disclosures about plan assets of a defined benefit pension or other postretirement plan. The objectives of the disclosures are to disclose the following: (i) how investment allocation decisions are made, including the factors that are pertinent to an understanding of investment policies and strategies; (ii) major categories of plan assets; (iii) inputs and valuation techniques used to measure the fair value of plan assets; (iv) effect of fair value measurements using significant unobservable inputs (Level 3) on changes in plan assets for the period; and (v) significant concentrations of risk within plan assets. ASC 820 allows the reporting entity, as a practical expedient, to measure the fair value of investments that do not have readily determinable fair values on the basis of the net asset value per share of the investment if the net asset value of the investment is calculated in a matter consistent with ASC 946, “Financial Services – Investment Companies”. The standard requires disclosures about the nature and risk of the investments and whether the investments are probable of being sold at amounts different from the net asset value per share. The following table sets forth by level, within the fair value hierarchy, the qualified pension plan as of December 31, 2024, and 2023: Recurring Fair Value Measures Recurring Fair Value Measures December 31, 2024 December 31, 2023 (Dollars in Thousands) Level 1 Level 2 Other Total Level 1 Level 2 Other Total Assets: Common Stock: Domestic $ 117,183 $ 199 $ — $ 117,382 $ 130,288 $ 281 $ — $ 130,569 Foreign 14,050 — — 14,050 13,767 — — 13,767 Government Securities 100,126 13,172 — 113,298 73,243 12,709 — 85,952 Corporate Securities: Domestic — 17,807 — 17,807 — 14,787 — 14,787 Foreign — 15,004 — 15,004 — 8,829 — 8,829 Mutual Funds 75,186 — — 75,186 81,130 — — 81,130 Cash and cash equivalents 5,263 (6,323) — (1,060) 2,846 236 — 3,082 Investments measured at NAV: Collective Investment Funds — — 321,937 321,937 — — 297,780 297,780 Partnership — — 90,308 90,308 — — 91,845 91,845 Mutual Funds — — 57,187 57,187 — — 48,116 48,116 Other — — 2,045 2,045 — — 128 128 Net (payable) receivable — — (50,454) (50,454) — — (29,974) (29,974) Total assets $ 311,808 $ 39,859 $ 421,023 $ 772,690 $ 301,274 $ 36,842 $ 407,895 $ 746,011 The following table sets forth by level, within the fair value hierarchy, the Other Benefits plan assets which consist of insurance benefits for retired employees, at fair value: Recurring Fair Value Measures Recurring Fair Value Measures December 31, 2024 December 31, 2023 (Dollars in Thousands) Level 1 Level 2 Other Total Level 1 Level 2 Other Total Assets: Mutual fund $ — $ 4,785 $ — $ 4,785 $ — $ 5,085 $ — $ 5,085 Total assets $ — $ 4,785 $ — $ 4,785 $ — $ 5,085 $ — $ 5,085 The following discussion provides information regarding the methods used in valuation of the various asset class investments held for the pension and other postretirement benefit plans. • Mutual funds classified as Level 1 securities have pricing inputs that are based on quoted prices in an active market. Principal markets for equity prices include published exchanges such as NASDAQ and New York Stock Exchange (NYSE). Mutual fund assets not included in the fair value hierarchy are privately held funds. These funds are not actively traded and utilize net asset value (NAV) as a practical expedient to measure fair value. • Common stock investments are traded in active markets on national and international securities exchanges and are valued at closing prices on the last business day of each period presented. They are classified as Level 1 securities. • Corporate and some government debt securities are valued using pricing models maximizing the use of observable inputs for similar securities. This includes basing value on yields currently available on comparable securities of issuers with similar credit ratings. Some government debt securities have quoted prices such as certain treasury securities and are classified as Level 1 securities. • Cash and cash equivalents comprise mostly of money market funds and foreign currency held. Money market funds are classified as Level 1 instruments as pricing inputs are based on unadjusted prices in an active market while foreign currency held is classified as a Level 2 investment based on inputs that are indirectly observable. • Investments in collective trust funds and partnerships are stated at the NAV as determined by the issuer of the fund and are based on the fair value of the underlying investments held by the fund less its liabilities. The NAV is used as a practical expedient to estimate fair value. These funds are primarily invested in a blend of corporate and government debt securities as well as international equities.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2024
Income Tax Disclosure [Abstract]
Income Taxes	(14) Income Taxes The details of income tax (benefit) expense are as follows: Puget Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Charged to operating expenses: Current: Federal $ 31,101 $ 66,086 $ 41,198 State 364 1,317 628 Deferred: Federal (875) (94,860) 17,866 State 133 23 6 Total income tax expense $ 30,723 $ (27,434) $ 59,698 Puget Sound Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Charged to operating expenses: Current: Federal $ 61,924 $ 112,168 $ 81,597 State 889 1,626 869 Deferred: Federal (10,226) (120,397) (2,171) State — — — Total income tax expense $ 52,587 $ (6,603) $ 80,295 The following reconciliation compares pre-tax book income at the federal statutory rate of 21.0% to the actual income tax expense in the Consolidated Statements of Income: Puget Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Income taxes at the statutory rate $ 63,256 21.0 % $ 5,524 21.0 % $ 99,549 21.0 % Increase (decrease): Utility plant differences 1 $ (29,712) (9.9) % $ (23,806) (90.5) % $ (23,028) (4.9) % AFUDC, net (5,704) (1.9) (4,017) (15.3) (3,567) (0.8) % Executive compensation 2,209 0.7 1,544 5.9 1,821 0.4 % Treasury grant amortization (797) (0.3) (750) (2.9) (5,717) (1.2) % Excess deferred tax amortization — — (8,689) (33.0) (13,722) (2.9) % State taxes, net 393 0.1 1,070 4.1 505 0.1 % Other–net 1,078 0.4 1,690 6.4 3,857 0.9 % Total income tax expense $ 30,723 10.1 % $ (27,434) (104.3) % $ 59,698 12.6 % Puget Sound Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Income taxes at the statutory rate $ 84,835 21.0 % $ 26,136 21.0 % $ 119,962 21.0 % Increase (decrease): Utility plant differences 1 $ (29,712) (7.4) % $ (23,806) (19.1) % $ (23,028) (4.0) % AFUDC, net (5,704) (1.4) % (4,017) (3.2) % (3,567) (0.6) % Excess deferred tax amortization — — % (8,689) (7.0) % (13,722) (2.4) % State taxes, net 702 0.2 % 1,291 1.0 % 689 0.1 % Other–net 2,466 0.6 % 2,482 2.0 % (39) — % Total income tax expense $ 52,587 13.0 % $ (6,603) (5.3) % $ 80,295 14.1 % _______________ 1. Utility plant differences include the reversal of excess deferred taxes using the average rate assumption method in the amount of $29.8 million, $27.8 million and $27.2 million in 2024, 2023 and 2022, respectively. The Company’s net deferred tax liability at December 31, 2024, and 2023, is composed of amounts related to the following types of temporary differences: Puget Energy At December 31, (Dollars in Thousands) 2024 2023 Utility plant and equipment $ 1,768,358 $ 1,799,505 Other deferred tax liabilities 466,317 407,842 Subtotal deferred tax liabilities 2,234,675 2,207,347 Net operating loss carryforward (201,562) (210,238) Net regulatory liability for income taxes (721,907) (760,961) Other deferred tax assets (313,526) (285,919) Subtotal deferred tax assets (1,236,995) (1,257,118) Total net deferred tax liabilities $ 997,680 $ 950,229 Puget Sound Energy At December 31, (Dollars in Thousands) 2024 2023 Utility plant and equipment $ 1,763,456 $ 1,796,476 Other deferred tax liabilities 382,968 319,328 Subtotal deferred tax liabilities 2,146,424 2,115,804 Net regulatory liability for income taxes (722,558) (761,621) Other deferred tax assets (306,374) (275,336) Subtotal deferred tax assets (1,028,932) (1,036,957) Total net deferred tax liabilities $ 1,117,492 $ 1,078,847 The Company calculates its deferred tax assets and liabilities under ASC 740, “Income Taxes”. Deferred tax assets and liabilities are recognized based on temporary differences between the financial statement and tax bases of assets and liabilities using enacted tax rates expected to be in effect when these differences are realized. A valuation allowance is recorded when it is more likely than not that some portion or all of a deferred tax asset will not be realized. The ultimate realization of a deferred tax asset depends on the ability to generate sufficient taxable income of the appropriate character and in the appropriate taxing jurisdictions within the carryforward periods available. Puget Energy’s net operating loss carryforwards will expire at various dates between 2031 and 2037. Net operating losses generated in 2018 and thereafter have no expiration date. The Company believes that it is more likely than not that its deferred income tax assets as of December 31, 2024 will be realized, thus no material valuation allowance has been recorded. As of December 31, 2024, and 2023, the Company had no material unrecognized tax benefits. As a result, no interest or penalties were accrued for unrecognized tax benefits during the year. The Company has open tax years from 2021 through 2024. The Company classifies interest as interest expense and penalties as other expense in the financial statements.

Litigation

Litigation	12 Months Ended
	Dec. 31, 2024
Jointly Owned Utility Plant Interests
Litigation	LitigationFrom time to time, the Company is involved in litigation or legislative rulemaking proceedings relating to its operations in the normal course of business.  As of December 31, 2024, the Company does not believe that it is involved in any pending proceedings material to the Company’s operations.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2024
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies For the year ended December 31, 2024, approximately 10.9% of the Company’s energy output was obtained at an average cost of approximately $0.067 per Kilowatt Hour (kWh) through long-term contracts with three of the Washington Public Utility Districts (PUDs) that own hydroelectric projects on the Columbia River. The purchase of power from the Columbia River projects is on a pro rata share basis under which the Company pays a proportionate share of the annual debt service, operating and maintenance costs and other expenses associated with each project, in proportion to the contractual share of power that PSE obtains from that project. In these instances, PSE’s payments are not contingent upon the projects being operable; therefore, PSE is required to make the payments even if power is not delivered. These projects are financed substantially through debt service payments and their annual costs should not vary significantly over the term of the contracts unless additional financing is required to meet the costs of major maintenance, repairs or replacements, or license requirements. The Company’s share of the costs and the output of the projects is subject to reduction due to various withdrawal rights of the PUDs and others over the contract lives. The Company's expenses under these PUD contracts were as follows for the years ended December 31: (Dollars in Thousands) 2024 2023 2022 PUD contract costs $ 211,800 $ 174,385 $ 149,575 As of December 31, 2024, the Company purchased portions of the power output of the PUDs' projects as set forth in the following table: Company's Share of (Dollars in Thousands) Contract 2025 Percent of Output 2025 Megawatt Capacity Estimated 2025 Total Costs 2025 Debt Service Costs Interest included in 2025 Debt Service Costs Debt Outstanding Chelan County PUD 1 : Rock Island Project 2051 40.0 % 252 $ 85,641 $ 20,499 $ 5,572 $ 98,638 Rocky Reach Project 2051 40.0 540 112,077 6,166 1,808 32,155 Douglas County PUD 2 : Wells Project 2032 18.6 156 42,883 — — — Grant County PUD 3 : Priest Rapids Development 2052 9.9 94 54,717 310 166 4,112 Wanapum Development 2052 9.9 121 54,717 310 166 4,112 Total 1,163 $ 350,035 $ 27,285 $ 7,712 $ 139,017 _______________ 1. PSE currently purchases output from Chelan County PUD's Rock Island and Rocky Reach hydroelectric projects under four separate contracts: 1) a contract for 25% of output that was executed in February 2006 and expires October 31, 2031. In 2023, PSE executed a new contract extending this 25% share of output through October 2051; 2) a contract executed in March 2021 for 5% of output that began on January 1, 2022 and continues through December 31, 2026; 3) a contract executed during 2023 to purchase an additional 5% of output for each from January 1, 2024 through December 31, 2028; and 4) a contract executed during 2024 to purchase an additional 5% of output that begins on February 1, 2025 and continues through December 31, 2025. 2. PSE currently purchases output from Douglas County PUD's Wells hydroelectric project under three separate contracts: 1) a contract executed in March 2017 with a variable share output (average 13.1% in 2025) that began on September 1, 2018 and ends September 30, 2028; 2) a contract executed in March 2021 for 5.5% of output from October 1, 2021 through September 30, 2024. In 2023, PSE executed a new contract extending this 5.5% share of output through September 30, 2029; and 3) a contract executed in August 2024 for 9.5% to 18.9% share of output from January 1, 2026 through December 31, 2032. 3. PSE currently purchases output from Grant County PUD's Wanapum and Priest Rapids hydroelectric developments under four separate contracts: 1) a contract that was executed on December 13, 2001 and began November 1, 2005 under which PSE receives 0.64% of output through March 31, 2052; 2) a contract entered in June 2024 for 4.22% of output from the Annual Auction that begins on January 1, 2025, and continues through December 31, 2025; 3) a contract entered in April 2024 for 0.88% of output from the Eugene Water and Electric Board Meaningful Priority rights that begins on January 1, 2025, and continues through December 31, 2025 ; and 4) a contract entered in April 2024 for 4.13% of output from the Meaningful Priority rights that begins on January 1, 2025, and continues through December 31, 2025. PSE reserves the right to renew the latter contract on an annual basis. The following table summarizes the Company’s estimated payment obligations for purchases from electric portfolio contracts and electric wholesale market transactions. These contracts have varying terms and may include escalation and termination provisions. (Dollars in Thousands) 2025 2026 2027 2028 2029 Thereafter Total Columbia River projects $ 350,035 $ 238,243 $ 226,541 $ 238,331 $ 171,203 $ 3,563,272 $ 4,787,625 Electric portfolio contracts 474,683 255,973 258,701 304,056 291,040 3,709,279 5,293,732 Electric wholesale market transactions 226,141 157,991 87,434 57,019 56,982 515,240 1,100,807 Total $ 1,050,859 $ 652,207 $ 572,676 $ 599,406 $ 519,225 $ 7,787,791 $ 11,182,164 Total purchased power contracts provided the Company with approximately 14.6 million, 14.7 million and 15.3 million MWhs of firm energy at a cost of approximately $1,006.3 million, $851.6 million and $892.7 million for the years 2024, 2023, and 2022, respectively. Natural Gas Supply Obligations The Company has entered into various firm supply, transportation and storage service contracts in order to ensure adequate availability of natural gas supply for its customers and generation requirements. The Company contracts for its long-term natural gas supply on a firm basis, which means the Company has a 100% daily take obligation and the supplier has a 100% daily delivery obligation to ensure service to PSE’s customers and generation requirements. The transportation and storage contracts, which have remaining terms from 1 year to 21 years, provide that the Company must pay a fixed demand charge each month, regardless of actual usage. The Company incurred demand charges of $125.0 million, $137.6 million, and $138.3 million for firm transportation, storage and peaking services for its natural gas customers for the years 2024, 2023, and 2022. The Company incurred demand charges of $71.1 million, $60.5 million, and $53.9 million for firm transportation, storage and peaking services for the natural gas supply for its combustion turbines for the years 2024, 2023, and 2022. The following table summarizes the Company’s obligations for future natural gas supply and demand charges through the primary terms of its existing contracts. The quantified obligations are based on the FERC and Canadian Energy Regulator (CER) currently authorized rates, which are subject to change. Natural Gas Supply and Demand Charge Obligations 2025 2026 2027 2028 2029 Thereafter Total Natural gas wholesale market transactions $ 517,802 $ 429,749 $ 277,306 $ 180,565 $ 79,714 $ — $ 1,485,136 Firm transportation service 167,274 165,151 166,716 163,261 144,884 669,602 1,476,888 Firm storage service 9,350 8,476 8,189 2,678 837 4,946 34,476 Total $ 694,426 $ 603,376 $ 452,211 $ 346,504 $ 225,435 $ 674,548 $ 2,996,500 Service Contracts The following table summarizes the Company’s estimated obligations for energy production service contracts through the terms of its existing contracts. Service Contract Obligations 2025 2026 2027 2028 2029 Thereafter Total Energy production service contracts $ 36,920 $ 40,184 $ 40,987 $ 41,823 $ 42,639 $ 60,494 $ 263,047 Legal Matters Washington Climate Commitment Act In 2021, the Washington Legislature adopted the CCA, which establishes a GHG emissions cap-and-invest program that requires covered entities, including electric and natural gas utilities, to purchase allowances to cover their GHG emissions with a cap on available allowances beginning on January 1, 2023 that declines annually through 2050. The WDOE published final regulations to implement the program on September 29, 2022, which became effective on October 30, 2022. The WDOE also indicated that there will be subsequent rulemakings building off initial rulemaking as program implementation proceeds. Compliance with the CCA requires covered entities to obtain allowances equal to their emissions and submit to the WDOE annually according to a staggered four-year compliance schedule. For the first three years of each compliance period, covered entities must submit allowances to cover at least 30% of their annual compliance obligation, as determined by the WDOE, no later than November 1st of the following year. For the fourth year of each compliance period, covered entities must submit sufficient allowances to cover 100% of their full four-year compliance obligation, as determined by the WDOE. The WDOE provided an initial allocation of no-cost allowances to electric utilities, including PSE, on April 24, 2023. However, qualifying electric utilities were allowed to submit revised emissions forecasts approved by the Washington Commission to WDOE. PSE filed its revised forecast of 2023 emission in Docket No. UE 220797, which was approved by the Washington Commission on July 27, 2023, and approved by the WDOE on September 27, 2023. On September 30, 2024, the WDOE provided notice to PSE that its 2023 annual compliance obligation was confirmed based on its 2023 reported covered emissions as previously reported to the WDOE. On October 16, 2024, the WDOE held a meeting with electric utilities, including PSE, regarding CCA compliance issues related to calendar year 2023, at which time WDOE stated that based on current information it will not make further adjustments (or “true up”) accounting for allocation methods, forecasts or cost burden associated with calendar year 2023 for any electric utilities, including PSE, except for administrative costs, at the current time. The WDOE also indicated that there will be future meetings with electric utilities on how the adjustment (or “true-up”) mechanism will work going forward and that the WDOE would provide electric utilities advance notice if any such adjustments were being considered. Based on the determinations made by the WDOE in the aforementioned notices, PSE recorded a compliance obligation of $26.2 million for allowances for electric operations as of December 31, 2024. Given the potential for future rulemakings and the WDOE's ability to adjust no-cost allowances during the compliance period, there is estimation uncertainty surrounding the Company's ability to estimate its compliance obligation both on an annual basis and a four-year compliance period, prior to a final WDOE determination. As existing uncertainties are resolved in future periods, any change in compliance costs as a result of such estimated additional liabilities would be deferred under ASC 980 as a regulatory asset consistent with Docket No. UE-220974, as these amounts will be recoverable from customers in future utility rates. As a result, there is no current impact to the Company's consolidated statements of income. Other Commitments and Contingencies For information regarding PSE's environmental remediation obligations, see Note 4, "Regulation and Rates," to the consolidated financial statements included in Item 8 of this report.

Accumulated Other Comprehensive

Accumulated Other Comprehensive Income (Loss)	12 Months Ended
	Dec. 31, 2024
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated Other Comprehensive Income (Loss)	Accumulated Other Comprehensive Income (Loss ) The following tables present the changes in the Company’s (loss) AOCI by component for the years ended December 31, 2024, 2023 and 2022, respectively: Puget Energy Net unrealized gain (loss) and prior service cost on pension plans Changes in AOCI, net of tax (Dollars in Thousands) Total Balance at December 31, 2021 $ (27,432) $ (27,432) Other comprehensive income (loss) before reclassifications (4,559) (4,559) Amounts reclassified from accumulated other comprehensive income (loss), net of tax 7,217 7,217 Net current-period other comprehensive income (loss) 2,658 2,658 Balance at December 31, 2022 $ (24,774) $ (24,774) Other comprehensive income (loss) before reclassifications 44,277 44,277 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (1,964) (1,964) Net current-period other comprehensive income (loss) 42,313 42,313 Balance at December 31, 2023 $ 17,539 $ 17,539 Other comprehensive income (loss) before reclassifications 27,866 27,866 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (2,237) (2,237) Net current-period other comprehensive income (loss) 25,629 25,629 Balance at December 31, 2024 $ 43,168 $ 43,168 Puget Sound Energy Net unrealized gain (loss) and prior service cost on pension plans Net unrealized gain (loss) on treasury interest rate swaps Changes in AOCI, net of tax (Dollars in Thousands) Total Balance at December 31, 2021 $ (108,541) $ (4,600) $ (113,141) Other comprehensive income (loss) before reclassifications (4,512) — (4,512) Amounts reclassified from accumulated other comprehensive income (loss), net of tax 14,223 386 14,609 Net current-period other comprehensive income (loss) 9,711 386 10,097 Balance at December 31, 2022 $ (98,830) $ (4,214) $ (103,044) Other comprehensive income (loss) before reclassifications 44,277 — 44,277 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (12) 385 373 Net current-period other comprehensive income (loss) 44,265 385 44,650 Balance at December 31, 2023 $ (54,565) $ (3,829) $ (58,394) Other comprehensive income (loss) before reclassifications 27,862 — 27,862 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (101) 386 285 Net current-period other comprehensive income (loss) 27,761 386 28,147 Balance at December 31, 2024 $ (26,804) $ (3,443) $ (30,247) Details about the reclassifications out of AOCI (loss) for the years ended December 31, 2024, 2023 and 2022, respectively, are as follows: Puget Energy (Dollars in Thousands) Details about accumulated other comprehensive income (loss) components Affected line item in the statement where net income (loss) is presented Amount reclassified from accumulated 2024 2023 2022 Net unrealized gain (loss) and prior service cost on pension plans: Amortization of prior service cost (a) $ (33) $ (172) $ (311) Amortization of net gain (loss) (a) 2,865 2,658 (8,824) Total before tax 2,832 2,486 (9,135) Tax (expense) or benefit (595) (522) 1,918 Net of tax 2,237 1,964 (7,217) Total reclassification for the period Net of tax $ 2,237 $ 1,964 $ (7,217) __________ (a) These AOCI components are included in the computation of net periodic pension cost, see Note 13, "Retirement Benefits," to the consolidated financial statements included in this Item 8 of this report for additional details. Puget Sound Energy (Dollars in Thousands) Details about accumulated other comprehensive income (loss) components Affected line item in the statement where net income (loss) is presented Amount reclassified from accumulated 2024 2023 2022 Net unrealized gain (loss) and prior service cost on pension plans: Amortization of prior service cost (a) $ (33) $ (172) $ (311) Amortization of net gain (loss) (a) 161 187 (17,693) Total before tax 128 15 (18,004) Tax (expense) or benefit (27) (3) 3,781 Net of tax 101 12 (14,223) Net unrealized gain (loss) on treasury interest rate swaps: Interest rate contracts Interest expense (487) (488) (488) Tax (expense) or benefit 101 103 102 Net of tax (386) (385) (386) Total reclassification for the period Net of tax $ (285) $ (373) $ (14,609) ____________ (a) These AOCI components are included in the computation of net periodic pension cost, see Note 13, "Retirement Benefits," to the consolidated financial statements included in this Item 8 of this report for additional details.

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2024
Segment Reporting [Abstract]
Segment Reporting Disclosure	Segment Information Puget Energy operates one reportable segment referred to as the regulated utility segment (PSE). PSE does not contain any additional reportable segments. The regulated utility operation generates, purchases and sells electricity and purchases, transports and sells natural gas. The service territory of PSE covers approximately 6,000 square miles in the state of Washington. Operations in addition to the Regulated Utility reportable segment, described as Other below, include the activities conducted at the holding company level and at Puget LNG, a non-regulated liquefied natural gas facility. The accounting policies of the Regulated Utility operating segment are the same as those described in Note 1, "Summary of Significant Accounting Policies" to the consolidated financial statements included in this Item 8 of this report. The chief operating decision maker for both Puget Energy and PSE is the president and chief executive officer. The chief operating decision maker assesses performance and decides resource allocation using net income for the Regulated Utility reportable segment. Net income is used by the chief operating decision maker to allocate resources, determine the Company’s availability to fund capital expenditures, and assess overall performance. The chief operating decision maker uses net income by comparing actual results to budget to assess Company performance. Puget Energy Year Ended December 31, 2024 (Dollars in Thousands) Regulated Utility Other Total Revenue $ 4,825,231 $ 30,984 $ 4,856,215 Depreciation and amortization 781,325 6,661 787,986 Income tax (benefit) expense 52,587 (21,864) 30,723 Non-utility expense and other 21,664 24,392 46,056 Interest expense (321,550) (110,644) (432,194) Net income 346,148 (80,893) 265,255 Total assets 17,026,384 1,934,007 18,960,391 Construction expenditures (1,608,947) (768) (1,609,715) Puget Energy Year Ended December 31, 2023 (Dollars in Thousands) Regulated Utility Other Total Revenue $ 4,786,618 $ 29,956 $ 4,816,574 Depreciation and amortization 744,629 6,706 751,335 Income tax (benefit) expense (6,603) (20,831) (27,434) Non-utility expense and other 28,658 27,857 56,515 Interest expense (285,148) (96,363) (381,511) Net income 131,059 (77,319) 53,740 Total assets 15,771,767 1,960,686 17,732,453 Construction expenditures (1,465,925) (640) (1,466,565) Puget Energy Year Ended December 31, 2022 (Dollars in Thousands) Regulated Utility Other Total Revenue $ 4,216,173 $ 4,989 $ 4,221,162 Depreciation & Amortization 657,349 5,883 663,232 Income Tax (Benefit) Expense 80,295 (20,597) 59,698 Non-utility expense and other 47,194 12,610 59,804 Interest expense (256,774) (91,147) (347,921) Net Income 490,952 (76,607) 414,345 Total assets 15,200,242 1,987,272 17,187,514 Construction expenditures (1,000,810) (3,903) (1,004,713) There are no significant segment expenses used by the chief operating decision maker to manage the segment’s operations that are not included in the Consolidated Statements of Income. PSE recognized revenue from Puget LNG for gas transportation services of $3.7 million, $1.1 million, and zero for years ended December 31, 2024, 2023 and 2022, respectively. These revenues are eliminated in Puget Energy's Consolidated Statements of Income. Puget LNG is charged tariffed rates that are approved by the Washington Commission.

SCHEDULE I CONDENSED FINANCIAL

SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PUGET ENERGY	12 Months Ended
	Dec. 31, 2024
Condensed Financial Information Disclosure [Abstract]
Schedule I: Condensed Financial Information of Puget Energy	SCHEDULE I: CONDENSED FINANCIAL INFORMATION OF PUGET ENERGY PUGET ENERGY, INC. CONDENSED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (Dollars in Thousands) Year Ended December 31, 2024 2023 2022 Non-utility expense and other $ (2,883) $ (1,466) $ (1,206) Other income (deductions): Equity in earnings of subsidiary 334,121 110,719 474,873 Interest income 18,439 17,863 8,458 Interest expense (103,019) (88,739) (84,051) Income tax benefit (expense) 18,597 15,363 16,271 Net income (loss) $ 265,255 $ 53,740 $ 414,345 Comprehensive income (loss) $ 290,884 $ 96,053 $ 417,003 See accompanying notes to the condensed financial statements. PUGET ENERGY, INC. CONDENSED BALANCE SHEETS (Dollars in Thousands) December 31, 2024 2023 Assets: Investment in subsidiaries $ 5,594,854 $ 5,096,133 Other property and investments: Goodwill 1,656,513 1,656,513 Current assets: Cash 817 1,596 Receivables from affiliates 1 256,671 256,417 Prepaid expenses and other 16 19 Income tax receivables 521 96 Total current assets 258,025 258,128 Long-term assets: Deferred income taxes 196,210 207,192 Other 1,891 2,673 Total long-term assets 198,101 209,865 Total assets $ 7,707,493 $ 7,220,639 Capitalization and liabilities: Common equity $ 5,368,205 $ 4,960,382 Long-term debt 1,590,795 1,988,609 Total capitalization 6,959,000 6,948,991 Current liabilities: Accounts payable to affiliates 1 195 153 Short-term debt 338,400 261,500 Current maturities of long-term debt 400,000 — Interest 9,898 9,995 Total current liabilities 748,493 271,648 Commitments and contingencies (Note 16) Total capitalization and liabilities $ 7,707,493 $ 7,220,639 _______________ 1 Eliminated in consolidation. See accompanying notes to the condensed financial statements. PUGET ENERGY, INC. CONDENSED STATEMENT OF CASH FLOWS (Dollars in Thousands) Year Ended December 31, 2024 2023 2022 Operating activities: Net cash provided by (used in) operating activities $ 96,588 $ 64,506 $ (10,197) Investing activities: Investment in subsidiaries (292,800) (100,000) (50,000) (Increase) decrease in loan to subsidiary (590) (9,753) (12,176) Net cash provided by (used in) investing activities (293,390) (109,753) (62,176) Financing activities: Dividends paid (175,861) (99,760) (16,230) Investment from Parent 292,800 — — Change in short-term debts, net 76,900 142,900 84,300 Issuance of long-term debts — — 448,075 Redemption of long-term debts — — (450,000) Issue costs and others 2,184 2,175 1,370 Net cash provided by (used in) by financing activities 196,023 45,315 67,515 Increase (decrease) in cash (779) 68 (4,858) Cash at beginning of year 1,596 1,528 6,386 Cash at end of year $ 817 $ 1,596 $ 1,528 See accompanying notes to the condensed financial statements. NOTES TO CONDENSED FINANCIAL STATEMENTS (1) Basis of Presentation Puget Energy is an energy services holding company that conducts substantially all of its business operations through its regulated subsidiary, PSE. Puget Energy also has a wholly-owned non-regulated subsidiary, Puget LNG, which was formed in November 2016, and has the sole purpose of owning, operating and financing the non-regulated activity of the LNG facility at the Port of Tacoma, Washington. These condensed financial statements and related footnotes have been prepared in accordance with Rule 12-04, Schedule I of Regulation S-X. These financial statements, in which Puget Energy’s subsidiaries have been included using the equity method, should be read in conjunction with the consolidated financial statements and notes thereto of Puget Energy included in Item 8, "Financial Statements and Supplementary Data" of this report. Puget Energy owns 100% of the common stock of its subsidiaries. Equity earnings of subsidiary included earnings from PSE and Puget LNG of $338.1 million, $114.8 million and $473.8 million for the years ended December 31, 2024, 2023, and 2022, respectively, and business combination accounting adjustments under ASC 805 recorded at Puget Energy for PSE of $(4.0) million, $(4.1) million and $1.0 million for the years ended December 31, 2024, 2023, and 2022, respectively. Investment in subsidiaries includes Puget Energy business combination accounting adjustments under ASC 805 that are recorded at Puget Energy. (2) Long-Term Debt For information concerning Puget Energy’s long-term debt obligations, see Note 7, "Long-Term Debt" to the consolidated financial statements included in Item 8 of this report. (3) Commitments and Contingencies For information concerning Puget Energy’s material contingencies and guarantees, see Note 16, "Commitments and Contingencies" to the consolidated financial statements included in Item 8 of this report.

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 265,255	$ 53,740	$ 414,345

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Dec. 31, 2024
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false

Insider Trading Policies and Pr

Insider Trading Policies and Procedures	12 Months Ended
	Dec. 31, 2024
Insider Trading Policies and Procedures [Line Items]
Insider Trading Policies and Procedures Adopted	true

Cybersecurity Risk Management a

Cybersecurity Risk Management and Strategy Disclosure	12 Months Ended
	Dec. 31, 2024
Cybersecurity Risk Management, Strategy, and Governance [Line Items]
Cybersecurity Risk Management Processes for Assessing, Identifying, and Managing Threats [Text Block]	PSE maintains a comprehensive business continuity plan that includes the identification, assessment and management of risks arising from various avenues, including cyber. Business continuity includes action plans to respond to and remedy information technology (IT) outages, attacks, and other cyber threats, which are maintained between two specific plans, the IT disaster recovery plan and the cybersecurity incident response plan (CSIRP). The CSIRP specifies guidance for various cyber related risks to ensure business continuity and timely reporting of incidents to various governing bodies, including the SEC. The CSIRP is a perpetually updated plan that is managed by the Chief Information Security Officer (CISO) and Chief Information Officer (CIO). PSE's CIO has served in various roles in IT and IT security for over 15 years, including serving as Chief Operating Officer or Chief Information Officer primarily in the financial services industry. Further, the CIO holds an undergraduate degree in computer science. PSE's CISO has over 15 years of experience managing IT security across different industries and companies. Additionally, the CISO holds an undergraduate degree and has been a Certified Information Systems Security Professional for over 15 years. As part of the CSIRP, PSE maintains a standalone team of IT security and risk management professionals in the Cyber Defense Center (CDC). The CDC is responsible for implementing the CSIRP, including the identification and ongoing monitoring and response to all cyber events and risks, including risks associated with the Company’s use of third-party service providers, which impact the Company. To identify, defend, detect and respond to cyber events, PSE performs various on-going activities, such as, proactive privacy and cybersecurity reviews of systems and applications, monitoring threat intelligence information feeds, penetration testing to test security controls, conducting employee trainings, and monitoring emerging laws and regulations related to data protection and information security. Additionally, the Company conducts tabletop exercises to simulate our response to cybersecurity incidents. Depending on the nature of the incident, PSE may engage consultants, assessors, or other third-parties to assist in the assessment, testing, remediation, and/or management of cyber incidents. Once cyber incidents are identified, a risk assessment is performed by the CDC, in accordance with the CSIRP. The risk assessment includes quantitative and qualitative considerations determined by a committee of individuals, including, among others, the Controller, CISO and Chief Ethics and Compliance Officer, that report to the Chief Financial Officer, CIO, and Senior Vice President General Counsel and Chief Sustainability Officer. Any cyber incidents that exceed thresholds set in the CSIRP are then escalated to the aforementioned committee for a materiality assessment and disclosure considerations. The Company's Audit Committee oversees management's process for identifying and mitigating cybersecurity risks. Periodically, the CISO presents cyber incidents and risks to the audit committee as part of the board of directors' oversight of risks from cybersecurity threats. The Audit Committee's oversight includes understanding existing and new cybersecurity risks and status on management's response and mitigation plans.
Cybersecurity Risk Management Processes Integrated [Flag]	true
Cybersecurity Risk Management Processes Integrated [Text Block]	PSE maintains a comprehensive business continuity plan that includes the identification, assessment and management of risks arising from various avenues, including cyber.
Cybersecurity Risk Management Third Party Engaged [Flag]	true
Cybersecurity Risk Third Party Oversight and Identification Processes [Flag]	true
Cybersecurity Risk Materially Affected or Reasonably Likely to Materially Affect Registrant [Flag]	false
Cybersecurity Risk Board of Directors Oversight [Text Block]	PSE maintains a comprehensive business continuity plan that includes the identification, assessment and management of risks arising from various avenues, including cyber. Business continuity includes action plans to respond to and remedy information technology (IT) outages, attacks, and other cyber threats, which are maintained between two specific plans, the IT disaster recovery plan and the cybersecurity incident response plan (CSIRP). The CSIRP specifies guidance for various cyber related risks to ensure business continuity and timely reporting of incidents to various governing bodies, including the SEC. The CSIRP is a perpetually updated plan that is managed by the Chief Information Security Officer (CISO) and Chief Information Officer (CIO). PSE's CIO has served in various roles in IT and IT security for over 15 years, including serving as Chief Operating Officer or Chief Information Officer primarily in the financial services industry. Further, the CIO holds an undergraduate degree in computer science. PSE's CISO has over 15 years of experience managing IT security across different industries and companies. Additionally, the CISO holds an undergraduate degree and has been a Certified Information Systems Security Professional for over 15 years. As part of the CSIRP, PSE maintains a standalone team of IT security and risk management professionals in the Cyber Defense Center (CDC). The CDC is responsible for implementing the CSIRP, including the identification and ongoing monitoring and response to all cyber events and risks, including risks associated with the Company’s use of third-party service providers, which impact the Company. To identify, defend, detect and respond to cyber events, PSE performs various on-going activities, such as, proactive privacy and cybersecurity reviews of systems and applications, monitoring threat intelligence information feeds, penetration testing to test security controls, conducting employee trainings, and monitoring emerging laws and regulations related to data protection and information security. Additionally, the Company conducts tabletop exercises to simulate our response to cybersecurity incidents. Depending on the nature of the incident, PSE may engage consultants, assessors, or other third-parties to assist in the assessment, testing, remediation, and/or management of cyber incidents. Once cyber incidents are identified, a risk assessment is performed by the CDC, in accordance with the CSIRP. The risk assessment includes quantitative and qualitative considerations determined by a committee of individuals, including, among others, the Controller, CISO and Chief Ethics and Compliance Officer, that report to the Chief Financial Officer, CIO, and Senior Vice President General Counsel and Chief Sustainability Officer. Any cyber incidents that exceed thresholds set in the CSIRP are then escalated to the aforementioned committee for a materiality assessment and disclosure considerations. The Company's Audit Committee oversees management's process for identifying and mitigating cybersecurity risks. Periodically, the CISO presents cyber incidents and risks to the audit committee as part of the board of directors' oversight of risks from cybersecurity threats. The Audit Committee's oversight includes understanding existing and new cybersecurity risks and status on management's response and mitigation plans.
Cybersecurity Risk Board Committee or Subcommittee Responsible for Oversight [Text Block]	The Company's Audit Committee oversees management's process for identifying and mitigating cybersecurity risks. Periodically, the CISO presents cyber incidents and risks to the audit committee as part of the board of directors' oversight of risks from cybersecurity threats. The Audit Committee's oversight includes understanding existing and new cybersecurity risks and status on management's response and mitigation plans.
Cybersecurity Risk Process for Informing Board Committee or Subcommittee Responsible for Oversight [Text Block]	Once cyber incidents are identified, a risk assessment is performed by the CDC, in accordance with the CSIRP. The risk assessment includes quantitative and qualitative considerations determined by a committee of individuals, including, among others, the Controller, CISO and Chief Ethics and Compliance Officer, that report to the Chief Financial Officer, CIO, and Senior Vice President General Counsel and Chief Sustainability Officer. Any cyber incidents that exceed thresholds set in the CSIRP are then escalated to the aforementioned committee for a materiality assessment and disclosure considerations.
Cybersecurity Risk Role of Management [Text Block]	PSE maintains a comprehensive business continuity plan that includes the identification, assessment and management of risks arising from various avenues, including cyber. Business continuity includes action plans to respond to and remedy information technology (IT) outages, attacks, and other cyber threats, which are maintained between two specific plans, the IT disaster recovery plan and the cybersecurity incident response plan (CSIRP). The CSIRP specifies guidance for various cyber related risks to ensure business continuity and timely reporting of incidents to various governing bodies, including the SEC. The CSIRP is a perpetually updated plan that is managed by the Chief Information Security Officer (CISO) and Chief Information Officer (CIO). PSE's CIO has served in various roles in IT and IT security for over 15 years, including serving as Chief Operating Officer or Chief Information Officer primarily in the financial services industry. Further, the CIO holds an undergraduate degree in computer science. PSE's CISO has over 15 years of experience managing IT security across different industries and companies. Additionally, the CISO holds an undergraduate degree and has been a Certified Information Systems Security Professional for over 15 years. As part of the CSIRP, PSE maintains a standalone team of IT security and risk management professionals in the Cyber Defense Center (CDC). The CDC is responsible for implementing the CSIRP, including the identification and ongoing monitoring and response to all cyber events and risks, including risks associated with the Company’s use of third-party service providers, which impact the Company. To identify, defend, detect and respond to cyber events, PSE performs various on-going activities, such as, proactive privacy and cybersecurity reviews of systems and applications, monitoring threat intelligence information feeds, penetration testing to test security controls, conducting employee trainings, and monitoring emerging laws and regulations related to data protection and information security. Additionally, the Company conducts tabletop exercises to simulate our response to cybersecurity incidents. Depending on the nature of the incident, PSE may engage consultants, assessors, or other third-parties to assist in the assessment, testing, remediation, and/or management of cyber incidents. Once cyber incidents are identified, a risk assessment is performed by the CDC, in accordance with the CSIRP. The risk assessment includes quantitative and qualitative considerations determined by a committee of individuals, including, among others, the Controller, CISO and Chief Ethics and Compliance Officer, that report to the Chief Financial Officer, CIO, and Senior Vice President General Counsel and Chief Sustainability Officer. Any cyber incidents that exceed thresholds set in the CSIRP are then escalated to the aforementioned committee for a materiality assessment and disclosure considerations. The Company's Audit Committee oversees management's process for identifying and mitigating cybersecurity risks. Periodically, the CISO presents cyber incidents and risks to the audit committee as part of the board of directors' oversight of risks from cybersecurity threats. The Audit Committee's oversight includes understanding existing and new cybersecurity risks and status on management's response and mitigation plans.
Cybersecurity Risk Management Positions or Committees Responsible [Flag]	true
Cybersecurity Risk Management Positions or Committees Responsible [Text Block]	The CSIRP is a perpetually updated plan that is managed by the Chief Information Security Officer (CISO) and Chief Information Officer (CIO).
Cybersecurity Risk Management Expertise of Management Responsible [Text Block]	PSE's CIO has served in various roles in IT and IT security for over 15 years, including serving as Chief Operating Officer or Chief Information Officer primarily in the financial services industry. Further, the CIO holds an undergraduate degree in computer science. PSE's CISO has over 15 years of experience managing IT security across different industries and companies. Additionally, the CISO holds an undergraduate degree and has been a Certified Information Systems Security Professional for over 15 years.
Cybersecurity Risk Process for Informing Management or Committees Responsible [Text Block]	Once cyber incidents are identified, a risk assessment is performed by the CDC, in accordance with the CSIRP. The risk assessment includes quantitative and qualitative considerations determined by a committee of individuals, including, among others, the Controller, CISO and Chief Ethics and Compliance Officer, that report to the Chief Financial Officer, CIO, and Senior Vice President General Counsel and Chief Sustainability Officer. Any cyber incidents that exceed thresholds set in the CSIRP are then escalated to the aforementioned committee for a materiality assessment and disclosure considerations.
Cybersecurity Risk Management Positions or Committees Responsible Report to Board [Flag]	true

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2024
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Puget Energy is an energy services holding company that owns Puget Sound Energy (PSE). PSE is a public utility incorporated in the state of Washington that furnishes electric and natural gas services in a territory covering approximately 6,000 square miles, primarily in the Puget Sound region. Puget Energy also has a wholly-owned non-regulated subsidiary, Puget LNG, LLC (Puget LNG), which has the sole purpose of owning and operating the non-regulated activity of the Tacoma liquefied natural gas (LNG) facility. PSE and Puget LNG are considered related parties with similar ownership by Puget Energy. Therefore, capital and operating costs that are incurred by PSE and allocated to Puget LNG are related party transactions by nature. In 2009, Puget Holdings, LLC (Puget Holdings), owned by a consortium of long-term infrastructure investors, completed its merger with Puget Energy (the merger). As a result of the merger, all of Puget Energy’s common stock is indirectly owned by Puget Holdings. The acquisition of Puget Energy was accounted for in accordance with Financial Accounting Standards Board (FASB) Accounting Standards Codification (ASC) 805, “Business Combinations,” as of the date of the merger. ASC 805 requires the acquirer to recognize and measure identifiable assets acquired and liabilities assumed at fair value as of the merger date. The consolidated financial statements of Puget Energy reflect the accounts of Puget Energy and its subsidiaries. PSE’s consolidated financial statements include the accounts of PSE and its subsidiary. Puget Energy and PSE are collectively referred to herein as “the Company”. The consolidated financial statements are presented after elimination of all significant intercompany items and transactions. PSE’s consolidated financial statements continue to be accounted for on a historical basis and do not include any ASC 805. The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.
Utility Plant	Utility Plant Puget Energy and PSE capitalize, at original cost, additions to utility plant, including renewals and betterments. Costs include indirect costs such as engineering, supervision, certain taxes, pension and other employee benefits and an allowance for funds used during construction (AFUDC). Replacements of minor items of property are included in maintenance expense. When the utility plant is retired and removed from service, the original cost of the property is charged to accumulated depreciation and costs associated with removal of the property, less salvage, are charged to the cost of removal regulatory liability. Construction Work in Progress Construction work in progress represents construction materials, progress payments on major equipment contracts, engineering costs, AFUDC and other costs directly associated with construction projects. Such costs classified as construction work in progress are included within utility plant on the balance sheet. At completion of such projects, these costs are transferred to utility plant in service. Capitalized costs associated with construction activities are charged to operations and maintenance expenses when recoverability is no longer probable. Planned Major Maintenance Planned major maintenance is an activity that typically occurs when PSE overhauls or substantially upgrades various systems and equipment on a scheduled basis. Costs related to planned major maintenance are deferred and amortized to the next scheduled major maintenance. This accounting method also follows the Washington Commission regulatory treatment related to these generating facilities. Other Property and Investments For PSE, the costs of other property and investments (i.e., non-utility) are stated at historical cost. Expenditures for refurbishment and improvements that significantly add to productive capacity or extend useful life of an asset are capitalized. Replacements of minor items are expensed on a current basis. Gains and losses on assets sold or retired, which were previously recorded in utility plant, are apportioned between regulatory assets/liabilities and earnings. However, gains and losses on assets sold or retired, not previously recorded in utility plant, are reflected in earnings.
Depreciation and Amortization	Depreciation and Amortization The Company provides for depreciation and amortization on a straight-line basis. Amortization is recorded for finance leases, intangibles such as certain regulatory assets and liabilities, computer software and franchises. The annual depreciation provision stated as a percent of a depreciable electric utility plant was 3.4%, 3.4%, and 3.4% in 2024, 2023, and 2022, respectively; depreciable natural gas utility plant was 3.2%, 3.2%, and 2.9% in 2024, 2023, and 2022, respectively; and depreciable common utility plant was 6.6%, 6.5% and 7.1% in 2024, 2023, and 2022, respectively. The cost of removal is collected from PSE’s customers through depreciation expense and any excess is recorded as a regulatory liability.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents consist of demand bank deposits and short-term highly liquid investments with original maturities of three months or less at the time of purchase. The carrying amounts of cash and cash equivalents are reported at cost and approximate fair value, due to the short-term maturity.
Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy	Restricted Cash Restricted cash amounts primarily represent cash posted as collateral for derivative contracts as well as funds required to be set aside for contractual obligations related to transmission and generation facilities.
Materials and Supplies	Materials and Supplies Materials and supplies are used primarily in the operation and maintenance of electric and natural gas distribution and transmission systems as well as spare parts for combustion turbines used for the generation of electricity. The Company records these items at weighted-average cost.
Fuel and Gas Inventory	Fuel and Natural Gas Inventory
Regulatory Assets and Liabilities	Regulatory Assets and Liabilities PSE accounts for its regulated operations in accordance with ASC 980, “Regulated Operations” (ASC 980). ASC 980 requires PSE to defer certain costs or losses that would otherwise be charged to expense, if it is probable that future rates will permit recovery of such costs. It similarly requires deferral of revenues or gains that are expected to be returned to customers in the future. Accounting under ASC 980 is appropriate as long as rates are established by or subject to approval by independent third-party regulators; rates are designed to recover the specific enterprise’s cost of service; and in view of demand for service, it is reasonable to assume that rates set at levels that will recover costs can be charged to and collected from customers. In most cases, PSE classifies regulatory assets and liabilities as long-term when amortization periods extend longer than one year. For further details regarding regulatory assets and liabilities, see Note 4, "Regulation and Rates" to the consolidated financial statements included in Item 8 of this report. Puget Energy recorded regulatory assets and liabilities at the time of the merger related to power purchase contracts.
Allowance for Funds Used During Construction	Allowance for Funds Used During Construction AFUDC represents the cost of both the debt and equity funds used to finance utility plant additions during the construction period. The amount of AFUDC recorded in each accounting period varies depending primarily upon the level of construction work in progress and the rate used. AFUDC is capitalized as a part of the cost of utility plant; the debt portion is credited to interest expense, while the equity portion is credited to other income. Cash inflow related to AFUDC does not occur until these charges are reflected in rates. The Washington Commission authorized an AFUDC rate, which is calculated using its allowed rate of return for utility plant additions. The AFUDC rate authorized was 7.39% effective October 1, 2020 for natural gas and October 15, 2020 for electric. Per the 2022 GRC, the AFUDC rate authorized is 7.16% effective January 7, 2023 for natural gas and January 11, 2023 for electric. Per the 2024 GRC, the AFUDC rate authorized is 7.52% in 2025 and 7.64% in 2026 effective January 29, 2025. To the extent amounts calculated using this rate exceed the AFUDC calculated rate using the FERC formula, PSE capitalizes the excess as a deferred asset, crediting other income. The deferred asset is being amortized over the average useful life of PSE’s non-project electric utility plant, which is approximately 30 years.
Revenue Recognition	Revenue Recognition Operating utility revenue is recognized when the basis of services is rendered, which includes estimated unbilled revenue. Revenue from retail sales is billed based on tariff rates approved by the Washington Commission. PSE's estimate of unbilled revenue is based on a calculation using meter readings from its automated meter reading system. The estimate calculates unbilled usage at the end of each month as the difference between the customer meter readings on the last day of the month and the last customer meter readings billed. The unbilled usage is then priced at published rates for each tariff rate schedule to estimate the unbilled revenues by customer. PSE collected Washington excise taxes (which are a component of general retail customer rates) and municipal taxes totaling $329.9 million, $319.1 million and $292.8 million for 2024, 2023, and 2022, respectively. The Company reports the collection of such taxes on a gross basis in operation revenue and as expense in taxes other than income taxes in the accompanying consolidated statements of income. PSE's electric and natural gas operations contain a revenue decoupling mechanism under which PSE's actual energy delivery revenues related to electric transmission and distribution, natural gas operations and general administrative costs are compared with authorized revenues allowed under the mechanism. The mechanism mitigates volatility in revenue and gross margin erosion due to weather and energy efficiency. Any differences in revenue are deferred to a regulatory asset for under recovery or regulatory liability for over recovery under alternative revenue recognition standard. Revenue is recognized under this program when deemed collectible within 24 months based on alternative revenue recognition guidance. Decoupled rate increases are effective May 1 of each year subject to a soft rate cap of total revenue for decoupled rate schedules, where rate cap is applied to under-collected revenue and any over-collected revenues are passed back to customers at 100%. Any excess under-recovered revenue above the rate cap will be included in the following year's decoupled rate and the Company will only be able to recognize revenue below the rate cap of total revenue for decoupled rate schedules. For revenue deferrals exceeding the annual rate cap of total revenue for decoupled rate schedules, the Company will assess the excess amount to determine its ability to be collected within 24 months per GAAP rules. The soft rate cap test, which limits the amount of revenues PSE can collect in its annual filings, is 5.0% for natural gas customers and 3.0% for electric customers. The Company will not record any decoupling revenue that is expected to take longer than 24 months to collect following the end of the annual period in which the revenues would have otherwise been recognized. Once determined to be collectible within 24 months, any previously non-recognized amounts will be recognized. Revenues associated with energy costs under the PCA mechanism and PGA mechanism are excluded from the decoupling mechanism.
Allowance for Doubtful Accounts	Allowance for Credit Losses The Company measures expected credit losses on trade receivables on a collective basis by receivable type, which include electric retail receivables, gas retail receivables, and electric wholesale receivables. The estimate of expected credit losses considers historical credit loss information that is adjusted for current conditions and reasonable and supportable forecasts. The following table presents the activity in the allowance for credit losses for accounts receivable at December 31, 2024, and 2023: Puget Energy and (Dollars in Thousands) Year Ended December 31, Allowance for credit losses: 2024 2023 Beginning balance $ 38,211 $ 41,962 Provision for credit loss expense 1 43,573 34,724 Receivables charged-off (41,348) (38,475) Total ending allowance balance $ 40,436 $ 38,211 _____________ 1 $37.1 million and $17.1 million of provision related to balances of deferred costs specific to COVID-19 as of December 31, 2024 and 2023, respectively.
Federal Income Taxes	Federal Income Taxes For presentation in Puget Energy's and PSE’s separate financial statements, income taxes are allocated to the subsidiaries on the basis of separate company computations of tax, modified by allocating certain consolidated group limitations which are attributed to the separate company. Taxes payable or receivable are settled with Puget Holdings, which is the ultimate taxpayer.
Natural Gas Off System Sales and Capacity Release	Natural Gas Off-System Sales and Capacity Release PSE contracts for firm natural gas supplies and holds firm transportation and storage capacity sufficient to meet the expected peak winter demand for natural gas by its firm customers. Due to the variability in weather, winter peaking consumption of natural gas by most of its customers and other factors, PSE holds contractual rights to natural gas supplies and transportation and storage capacity in excess of its average annual requirements to serve firm customers on its distribution system. For much of the year, there is excess capacity available for third-party natural gas sales, exchanges and capacity releases. PSE sells excess natural gas supplies, enters into natural gas supply exchanges with third parties outside of its distribution area and releases to third parties excess interstate natural gas pipeline capacity and natural gas storage rights on a short-term basis to mitigate the costs of firm transportation and storage capacity for its core natural gas customers. The proceeds from such activities, net of transactional costs, are accounted for as reductions in the cost of purchased natural gas and passed on to customers through the PGA mechanism, with no direct impact on net income. As a result, PSE nets the sales revenue and associated cost of sales for these transactions in purchased natural gas.
Non-Core Gas Sales	As part of the Company’s electric operations, PSE purchases natural gas for its gas-fired generation facilities. The projected volume of natural gas for power is relative to the price of natural gas. Based on the market prices for natural gas, PSE may use the natural gas it has already purchased to generate power or PSE may sell the already purchased natural gas. The net proceeds from selling natural gas, previously purchased for power generation, are accounted for in electric operating revenue and are included in the PCA mechanism.
Accounting for Derivatives	Accounting for Derivatives ASC 815, "Derivatives and Hedging" (ASC 815), requires that all contracts considered to be derivative instruments be recorded on the balance sheet at their fair value unless the contracts qualify for an exception. PSE enters into derivative contracts to manage its energy resource portfolio and interest rate exposure including forward physical and financial contracts and swaps. Some of PSE’s physical electric supply contracts qualify for the NPNS exception to derivative accounting rules. PSE may enter into financial fixed price contracts to economically hedge the variability of certain index-based contracts. Those contracts that do not meet the NPNS exception are marked-to-market to current earnings in the statements of income, subject to deferral under ASC 980, for natural gas related derivatives due to the PGA mechanism. On December 19, 2024, the Washington Commission approved the Company's accounting petition in Docket No. UE-240773 to defer any incurred unrealized gains or losses on derivative instruments entered into to serve electric customers, and as such PSE has recognized regulatory assets and/or liabilities, thus deferring the unrealized gains or losses. As of December 31, 2024, the fair value of these derivatives were recorded on the Company's balance sheet as a derivative asset of $38.8 million and a derivative liability of $389.9 million. The difference of $351.1 million has been recorded as a regulatory asset in accordance with the accounting treatment approved by the Washington Commission.
Fair Value Measurements of Derivatives	Fair Value Measurements of Derivatives ASC 820, “Fair Value Measurements and Disclosures” (ASC 820), defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). As permitted under ASC 820, the Company utilizes a mid-market pricing convention (the mid-point price between bid and ask prices) as a practical expedient for valuing the majority of its assets and liabilities measured and reported at fair value. The Company utilizes market data or assumptions that market participants would use in pricing the asset or liability, including assumptions about risk and the risks inherent in the inputs to the valuation technique. These inputs can be readily observable, market corroborated or generally unobservable. The Company primarily applies the market approach for recurring fair value measurements as it believes that approach is used by market participants for these types of assets and liabilities. Accordingly, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs. The Company values derivative instruments based on daily quoted prices from an independent external pricing service. When external quoted market prices are not available for derivative contracts, the Company uses a valuation model that uses volatility assumptions relating to future energy prices based on specific energy markets and utilizes externally available forward market price curves. All derivative instruments are sensitive to market price fluctuations that can occur on a daily basis. For additional information, see Note 11, "Fair Value Measurements" to the consolidated financial statements included in Item 8 of this report.
Debt Related Costs	Debt-Related Costs Debt premiums, discounts, expenses and amounts received or incurred to settle hedges are amortized over the life of the related debt for the Company. The premiums and costs associated with reacquired debt are deferred and amortized over the life of the related new issuance, in accordance with ratemaking treatment for PSE and presented net of long-term liabilities on the balance sheet.
Lessee, Leases	Leases PSE determines if an arrangement is, or contains, a lease at inception of the contract. If the arrangement is, or contains a lease, PSE assesses whether the lease is operating or financing for income statement and balance sheet classification. Operating leases are included in operating lease right-of-use (ROU) assets, operating lease current liabilities, and operating lease liabilities in our consolidated balance sheets. Finance leases are included in utility plant, other current liabilities, and finance lease liabilities in our consolidated balance sheets. ROU assets represent the right to use an underlying asset for the lease term, and consist of the amount of the initial measurement of the lease liability, any lease payments made to the lessor at or before the commencement date, minus any lease incentives received, and any initial direct costs incurred by the lessee. Lease liabilities represent our obligation to make lease payments arising from the lease and are measured at present value of the lease payments not yet paid, discounted using the discount rate for the lease, determined based on PSE's incremental borrowing rate, at commencement. As most of PSE's leases do not provide an implicit interest rate, PSE uses the incremental borrowing rate based on the information available at commencement date in determining the present value of lease payments. For fleet, IT and wind farm land leases, this rate is applied using a portfolio approach. The lease terms may include options to extend or terminate the lease when it is reasonably certain that PSE will exercise that option. On the statement of income, operating leases are generally accounted for under a straight-line expense model, while finance leases, which were previously referred to as capital leases, are generally accounted for under a financing model. Consistent with the previous lease guidance, however, the standard allows rate-regulated utilities to recognize expense consistent with the timing of recovery in rates.
Consolidation, Variable Interest Entity, Policy	Variable Interest Entities In April 2017, PSE entered into a power purchase agreement (PPA) with Skookumchuck Wind Energy Project, LLC (Skookumchuck) pursuant to which Skookumchuck would develop a wind generation facility and sell bundled energy and associated attributes, namely renewable energy certificates (RECs), to PSE over a term of 20 years. Skookumchuck commenced commercial operation in November 2020. In May 2020, PSE entered into a PPA with Golden Hills Wind Farm, LLC (Golden Hills) pursuant to which Golden Hills would develop a wind generation facility and sell bundled energy and associated attributes, namely RECs, to PSE over a term of 20 years. On April 29, 2022, Golden Hills commenced commercial operations. In February 2021, PSE entered into a PPA with Clearwater Wind Project, LLC (Clearwater) in which Clearwater would develop a wind generation facility and sell energy and associated attributes to PSE over a term of 25 years. On November 8, 2022, Clearwater commenced commercial operations. For each of the aforementioned PPAs, PSE has no equity investment in the generation facilities, but is the only customer of each facility. PSE has concluded that Skookumchuck, Golden Hills and Clearwater represent VIE and that PSE is not the primary beneficiary of these VIEs since it does not control the commercial and operating activities of the facilities. Additionally, PSE does not have the obligation to absorb losses or receive benefits. As a result, PSE does not consolidate the VIEs. Purchased energy of $88.9 million, $86.0 million and $38.6 million
Self Insurance Reserve	Self-Insurance PSE is self-insured for storm damage and certain environmental contamination associated with current operations occurring on PSE-owned property. In addition, PSE is required to meet a deductible for a portion of the risk associated with comprehensive liability, workers’ compensation claims and catastrophic property losses other than those which are storm related. The cumulative annual cost threshold for the storm loss deferral mechanism under the 2017 GRC is $10.0 million. Under the 2024 GRC, the cumulative annual cost threshold for the storm loss deferral mechanism is $9.4 million in 2025 and $9.6 million in 2026. Additionally, costs may only be deferred if the outage meets the Institute of Electrical and Electronics Engineers outage criteria for system average interruption duration index and qualifying costs exceed $0.5 million per qualified storm.
Segment Reporting, Policy	Puget Energy operates one reportable segment referred to as the regulated utility segment (PSE). PSE does not contain any additional reportable segments. The regulated utility operation generates, purchases and sells electricity and purchases, transports and sells natural gas. The service territory of PSE covers approximately 6,000 square miles in the state of Washington. Operations in addition to the Regulated Utility reportable segment, described as Other below, include the activities conducted at the holding company level and at Puget LNG, a non-regulated liquefied natural gas facility. The accounting policies of the Regulated Utility operating segment are the same as those described in Note 1, "Summary of Significant Accounting Policies" to the consolidated financial statements included in this Item 8 of this report. The chief operating decision maker for both Puget Energy and PSE is the president and chief executive officer.

Accounting Policies (Tables)

Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2024
Accounting Policies [Abstract]
Accounts Receivable, Allowance for Credit Loss	The following table presents the activity in the allowance for credit losses for accounts receivable at December 31, 2024, and 2023: Puget Energy and (Dollars in Thousands) Year Ended December 31, Allowance for credit losses: 2024 2023 Beginning balance $ 38,211 $ 41,962 Provision for credit loss expense 1 43,573 34,724 Receivables charged-off (41,348) (38,475) Total ending allowance balance $ 40,436 $ 38,211 _____________ 1 $37.1 million and $17.1 million of provision related to balances of deferred costs specific to COVID-19 as of December 31, 2024 and 2023, respectively.

Revenue (Tables)

Revenue (Tables)	12 Months Ended
	Dec. 31, 2024
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue [Table Text Block]	The following tables present disaggregated revenue from contracts with customers, and other revenue by major source for the years ended December 31, 2024, December 31, 2023, and December 31, 2022: Puget Energy and (Dollars in Thousands) Year Ended December 31, 2024 Revenue from contracts with customers: Electric Natural Gas Other 1 Total Retail Residential $ 1,677,599 $ 796,889 $ — $ 2,474,488 Commercial 1,159,596 367,988 — 1,527,584 Industrial 131,869 26,764 — 158,633 Other 23,601 — — 23,601 Wholesale 286,364 — — 286,364 Transmission and transportation 33,911 30,874 — 64,785 Miscellaneous 2 35,274 246,708 34,950 316,932 Total revenue from contracts with customers $ 3,348,214 $ 1,469,223 $ 34,950 $ 4,852,387 Total other revenue 3 (15,519) 19,347 — 3,828 Total operating revenue $ 3,332,695 $ 1,488,570 $ 34,950 $ 4,856,215 _____________ 1. Other includes $34.7 million of Puget LNG revenues recorded at Puget Energy. 2. Miscellaneous natural gas revenue includes $253.0 million for the regulatory offset of CCA auction proceeds passed back to customers. 3. Total other revenue includes revenues from derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Puget Energy and (Dollars in Thousands) Year Ended December 31, 2023 Revenue from contracts with customers: Electric Natural Gas Other 1 Total Retail Residential $ 1,514,149 $ 851,906 $ — $ 2,366,055 Commercial 1,071,385 383,431 — 1,454,816 Industrial 123,548 29,149 — 152,697 Other 21,199 — — 21,199 Wholesale 498,251 — — 498,251 Transmission and transportation 46,141 24,265 — 70,406 Miscellaneous 2 25,231 94,193 47,431 166,855 Total revenue from contracts with customers $ 3,299,904 $ 1,382,944 $ 47,431 $ 4,730,279 Total other revenue 3 45,963 40,332 — 86,295 Total operating revenue $ 3,345,867 $ 1,423,276 $ 47,431 $ 4,816,574 _____________ 1. Other includes $31.0 million of Puget LNG revenues recorded at Puget Energy 2. Miscellaneous natural gas revenue includes $98.4 million for the regulatory offset of CCA auction proceeds passed back to customers. 3. Total other revenue includes revenues from derivatives and alternative revenue programs that are not considered revenues from contracts with customers. Puget Energy and (Dollars in Thousands) Year Ended December 31, 2022 Revenue from contracts with customers: Electric Natural Gas Other 1 Total Retail Residential $ 1,381,858 $ 808,376 $ — $ 2,190,234 Commercial 981,170 352,243 — 1,333,413 Industrial 116,712 25,096 — 141,808 Other 18,759 — — 18,759 Wholesale 319,380 — — 319,380 Transmission and transportation 47,027 20,332 — 67,359 Miscellaneous 13,065 718 50,069 63,852 Total revenue from contracts with customers $ 2,877,971 $ 1,206,765 $ 50,069 $ 4,134,805 Total other revenue 2 83,486 2,871 — 86,357 Total operating revenue $ 2,961,457 $ 1,209,636 $ 50,069 $ 4,221,162 _____________ 1. Other includes $5.0 million of Puget LNG revenues recorded at Puget Energy 2. Total other revenue includes revenues from derivatives, PTC deferral revenue and alternative revenue programs that are not considered revenues from contracts with customers.
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction	Based on management’s best estimate, the Company expects to recognize this revenue over the following time periods: Puget Energy (Dollars in Thousands) 2025 2026 2027 2028 2029 Thereafter Total Remaining Performance Obligations $ 19,554 $ 19,454 $ 19,454 $ 19,454 $ 19,454 $ 82,681 $ 180,051

Regulation and Rates (Tables)

Regulation and Rates (Tables)	12 Months Ended
	Dec. 31, 2024
Regulatory Assets [Line Items]
Schedule of Net Regulatory Assets and Liabilities	Puget Energy Remaining Amortization Period December 31, (Dollars in Thousands) 2024 2023 Total PSE regulatory assets (a) $ 1,416,493 $ 1,211,978 Puget Energy acquisition adjustments: Regulatory assets related to power contracts 3 to 30 years 4,779 6,266 Total Puget Energy regulatory assets $ 1,421,272 $ 1,218,244 Total PSE regulatory liabilities (a) $ (1,855,642) $ (1,914,896) Puget Energy acquisition adjustments: Deferred income taxes 651 660 Regulatory liabilities related to power contracts 3 to 30 years (30,566) (46,924) Various other regulatory liabilities Varies (1,193) (1,264) Total Puget Energy regulatory liabilities $ (1,886,750) $ (1,962,424) Puget Energy net regulatory asset (liabilities) $ (465,478) $ (744,180) ____________________ (a) Puget Energy’s regulatory assets and liabilities include purchase accounting adjustments under ASC 805.
Schedule of Regulatory Assets	The following table summarizes changes in the Company's environmental remediation regulatory assets for the years ended December 31, 2024, and 2023: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Environmental remediation regulatory asset beginning balance $ 182,697 $ 141,893 Remediation cost amortization, net of recoveries (3,732) (4,521) Changes in estimates 1 1,280 45,325 Environmental remediation regulatory asset ending balance $ 180,245 $ 182,697 _______________ 1 .
Schedule of Regulatory Liabilities	The following table summarizes changes in the Company's environmental remediation liabilities for the years ended December 31, 2024, and 2023: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Environmental remediation liabilities beginning balance $ 180,440 $ 135,052 Payments made, net of recoveries (10) (495) Changes in estimates 1 725 45,883 Environmental remediation liabilities ending balance $ 181,155 $ 180,440 _______________ 1.
Subsidiaries [Member]
Regulatory Assets [Line Items]
Schedule of Net Regulatory Assets and Liabilities	The net regulatory assets and liabilities at December 31, 2024, and 2023, are included in the following tables: Puget Sound Energy Remaining Amortization Period December 31, (Dollars in Thousands) 2024 2023 PCA unrealized loss N/A $ 284,166 $ — Environmental remediation (a) 180,245 182,697 Storm damage costs electric 1 to 4 years 120,431 95,754 Automated meter reading 19 years 98,572 104,159 Energy conservation costs (a) 75,373 37,560 PGA unrealized loss N/A 66,929 80,376 PCA mechanism N/A 61,202 48,427 Baker Dam licensing operating and maintenance costs (b) 56,201 55,641 Deferred Washington Commission AFUDC 30 years 55,427 58,648 Decoupling deferrals and interest Less than 2 years 51,838 31,398 Chelan PUD contract initiation 6.8 years 48,435 55,523 Climate Commitment Act auction proceeds N/A 43,538 186,550 Washington Commission LNG N/A 38,070 42,247 Washington Commission COVID-19 N/A 37,089 17,097 Lower Snake River 12.4 years 35,429 43,220 Unamortized loss on reacquired debt 3 to 43 years 29,680 31,626 Regulatory filing fee deferral (c) 2 years 26,543 14,582 Various other regulatory assets (a) 107,325 126,473 Total PSE regulatory assets $ 1,416,493 $ 1,211,978 Cost of removal (d) $ (748,095) $ (682,058) Deferred income taxes (e) N/A (722,558) (761,621) Repurposed production tax credits N/A (110,746) (126,482) Climate Commitment Act recovery N/A (97,694) (84,485) Decoupling liability Less than 2 years (63,890) (60,664) PGA liability 2 years (58,657) (132,082) Bill discount rate deferral N/A (20,567) (6,579) Various other regulatory liabilities (a) (33,435) (60,925) Total PSE regulatory liabilities $ (1,855,642) $ (1,914,896) PSE net regulatory assets (liabilities) $ (439,149) $ (702,918) __________________ (a) Amortization periods vary depending on the timing of underlying transactions. (b) The FERC license requires PSE to incur various O&M expenses over the life of the 50 year license for Baker. The regulatory asset represents the net present value of future expenditures and will be offset by actual costs incurred. (c) Amortization period approved in 2024 GRC, beginning January 29, 2025. (d) The balance is dependent upon the cost of removal of underlying assets and the life of utility plant. (e) For additional information, see Note 14,"Income Taxes" to the consolidated financial statements included in Item 8 of this report.
Schedule of Graduated Scale of Rate Adjustment Mechanism	Effective January 1, 2017, the following graduated scale is used in the PCA mechanism: Company’s Share Customers' Share Annual Power Cost Variability Over Under Over Under Over or under collected up to $17 million 100 % 100 % — % — % Over or under collected between $17 million - $40 million 35 50 65 50 Over or under collected beyond $40 million 10 10 90 90
Schedule of PGA Receivable Payable	The following table presents the PGA mechanism balances and activity as of December 31, 2024 and December 31, 2023: Puget Energy and (Dollars in Thousands) Year Ended December 31, PGA (liability)/receivable balance and activity 2024 2023 PGA (liability)/receivable beginning balance $ (132,082) $ (3,536) Actual natural gas costs 416,067 404,897 Allowed PGA recovery (336,170) (521,882) Interest (6,472) (7,639) Refund from counterparty settlement — (3,922) PGA (liability)/receivable ending balance $ (58,657) $ (132,082)

Utility Plant (Tables)

Utility Plant (Tables)	12 Months Ended
	Dec. 31, 2024
Utility Plant [Abstract]
Schedule of Utility Plant	The following table presents electric, natural gas and common utility plant classified by account: Puget Energy Puget Sound Energy Utility Plant Estimated Useful Life 1 December 31, December 31, (Dollars in Thousands) (Years) 2024 2023 2024 2023 Distribution plant 7-65 $ 8,983,586 $ 8,298,893 $ 10,474,294 $ 9,804,018 Production plant 12-90 3,310,663 3,173,514 3,928,187 3,805,294 Transmission plant 44-75 1,908,891 1,595,566 2,015,060 1,701,878 General plant 5-75 805,960 717,017 826,918 738,996 Intangible plant (including capitalized software) 2 3-50 716,038 586,749 706,576 577,291 Plant acquisition adjustment N/A 242,827 242,826 282,792 282,792 Underground storage 25-60 50,047 46,761 63,004 60,171 Liquefied natural gas storage 25-50 256,144 224,337 257,909 226,208 Plant held for future use N/A 59,657 59,409 59,809 59,561 Recoverable cushion gas N/A 8,784 8,784 8,784 8,784 Plant not classified N/A 733,184 1,032,004 733,184 1,032,002 Finance leases, net of accumulated amortization 3 N/A 91,045 95,114 91,045 95,114 Less: accumulated provision for depreciation (5,101,926) (4,643,833) (7,382,662) (6,954,968) Subtotal $ 12,064,900 $ 11,437,141 $ 12,064,900 $ 11,437,141 Construction work in progress 1,577,695 1,156,265 1,577,695 1,156,265 Net utility plant $ 13,642,595 $ 12,593,406 $ 13,642,595 $ 12,593,406 _______________________ 1. Estimated Useful Life years have been approved in the 2022 GRC. 2. Intangible assets include capitalized software and franchise agreements with useful lives ranging between 3-10 years and 10-50 years, respectively. 3. At December 31, 2024, and 2023, accumulated amortization of finance leases at Puget Energy and PSE was $18.3 million and $13.2 million, respectively.
Schedule of Jointly Owned Utility Plants	Jointly owned generating plant service costs are included in utility plant service cost at the Company's ownership share. The Company provides financing for its ownership interest in the jointly owned utility plants. The following tables indicate the Company’s percentage ownership and the extent of the Company’s investment in jointly owned generating plants in service at December 31, 2024. These amounts are also included in the Utility Plant table above, with the exception of Puget Energy's portion of the Tacoma LNG facility, which is reported in the Puget Energy "Other property and investments" financial statement line item. The Company's share of fuel costs and operating expenses for plant in service are included in the corresponding accounts in the Consolidated Statements of Income. Puget Energy Jointly Owned Generating Plants Energy Source (Fuel) Company’s Ownership Share Plant in Service at Cost Construction Work in Progress Accumulated Depreciation Colstrip Units 3 & 4 Coal 25.00% $ 324,451 $ — $ (233,934) Frederickson 1 Natural Gas 49.85 68,006 — (32,767) Jackson Prairie Natural Gas 33.34 48,174 688 (14,196) Tacoma LNG Natural Gas various 497,290 3,545 (36,847) Puget Sound Energy Jointly Owned Generating Plants Energy Source (Fuel) Company’s Ownership Share Plant in Service at Cost Construction Work in Progress Accumulated Depreciation Colstrip Units 3 & 4 Coal 25.00% $ 581,467 $ — $ (490,950) Frederickson 1 Natural Gas 49.85 73,658 — (38,418) Jackson Prairie Natural Gas 33.34 63,004 688 (29,025) Tacoma LNG Natural Gas various 246,893 240 (17,916)
Schedule of Asset Retirement Obligations	Puget Energy and Puget Sound Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 ARO beginning balance $ 207,034 $ 209,406 New ARO recognized in the period 18,811 — Relief of liability (6,049) (5,998) Revisions in estimated cash flows 9,471 (2,206) Accretion expense 6,676 5,832 ARO ending balance $ 235,943 $ 207,034

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2024
Long-Term Debt, Unclassified [Abstract]
Schedule of Long-Term Debt Instruments	The following table presents outstanding long-term debt due dates and principal amounts, net of debt discount, issuance and other costs and fair value adjustments at December 31, 2024 and 2023: (Dollars in Thousands) December 31, Series Type Due 2024 2023 Puget Sound Energy: 7.150% First Mortgage Bond 2025 $ — $ 15,000 7.200% First Mortgage Bond 2025 — 2,000 7.020% Senior Secured Note 2027 300,000 300,000 7.000% Senior Secured Note 2029 100,000 100,000 3.900% Pollution Control Bond 2031 138,460 138,460 4.000% Pollution Control Bond 2031 23,400 23,400 5.330% Senior Secured Note 2034 400,000 — 5.483% Senior Secured Note 2035 250,000 250,000 6.724% Senior Secured Note 2036 250,000 250,000 6.274% Senior Secured Note 2037 300,000 300,000 5.757% Senior Secured Note 2039 350,000 350,000 5.795% Senior Secured Note 2040 325,000 325,000 5.764% Senior Secured Note 2040 250,000 250,000 4.434% Senior Secured Note 2041 250,000 250,000 5.638% Senior Secured Note 2041 300,000 300,000 4.300% Senior Secured Note 2045 425,000 425,000 4.223% Senior Secured Note 2048 600,000 600,000 3.250% Senior Secured Note 2049 450,000 450,000 2.893% Senior Secured Note 2051 450,000 450,000 4.700% Senior Secured Note 2051 45,000 45,000 5.448% Senior Secured Note 2053 400,000 400,000 5.685% Senior Secured Note 2054 400,000 — * Debt discount, issuance cost and other * (45,835) (39,813) Total PSE long-term debt $ 5,961,025 $ 5,184,047 Puget Energy: * Fair value adjustment of PSE long-term debt * $ (131,326) $ (139,834) 3.650% Senior Secured Note 2025 — 400,000 2.379% Senior Secured Note 2028 500,000 500,000 4.100% Senior Secured Note 2030 650,000 650,000 4.224% Senior Secured Note 2032 450,000 450,000 * Debt discount, issuance cost and other * (5,780) (7,571) Total Puget Energy long-term debt $ 7,423,919 $ 7,036,642 ___________________ *
Schedule of Maturities of Long-Term Debt	The principal amounts of long-term debt maturities for the next five years and thereafter are as follows: (Dollars in Thousands) 2025 2026 2027 2028 2029 Thereafter Total Maturities of: PSE $ 17,000 $ — $ 300,000 $ — $ 100,000 $ 5,606,860 $ 6,023,860 Puget Energy 400,000 — — 500,000 — 1,100,000 2,000,000 Total long-term debt $ 417,000 $ — $ 300,000 $ 500,000 $ 100,000 $ 6,706,860 $ 8,023,860

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2024
Lessee, Lease, Description [Line Items]
Lease, Cost	The components of lease cost were as follows: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Finance lease cost: Amortization of right-of-use asset $ 3,915 $ 3,891 Interest on lease liabilities 3,192 3,237 Total finance lease cost $ 7,107 $ 7,128 Operating lease cost 1 $ 24,993 $ 23,891 _______________ 1. Includes $1.7 million and $1.7 million allocated to Puget LNG at Puget Energy related to the Port of Tacoma lease for the years ended December 31, 2024 and December 31, 2023, respectively. Supplemental cash flow information related to leases was as follows: Puget Energy and Year Ended December 31, (Dollars in Thousands) 2024 2023 Cash paid for amounts included in the measurement of lease liabilities: Operating cash flow for operating leases $ 17,038 $ 15,990 Investing cash flow for operating leases 1 7,955 7,901 Operating cash flow for finance leases 3,192 3,237 Financing cash flow for finance leases 3,915 3,891 Non-cash disclosure upon commencement of new lease Right-of-use assets obtained in exchange for new operating lease liabilities $ 4,093 $ 10,462 Right-of-use assets obtained in exchange for new finance lease liabilities 1,832 1,245 Non-cash disclosure upon modification of existing lease Modification of operating lease right-of-use assets $ 1,996 $ 6,912 _______________ 1 Includes $1.7 million and $1.7 million allocated to Puget LNG at Puget Energy related to the Port of Tacoma lease for the years ended December 31, 2024 and December 31, 2023, respectively.
Assets and Liabilities, Lessee	Supplemental balance sheet information related to leases was as follows: Puget Energy and (Dollars in Thousands) At December 31, Operating Leases 2024 2023 Operating lease right-of-use asset $ 181,397 $ 194,321 Operating leases liabilities current $ 22,761 $ 21,629 Operating lease liabilities long-term 166,700 180,754 Total operating lease liabilities: $ 189,461 $ 202,383 Finance Leases Common plant $ 53,594 $ 55,756 Natural gas plant 310 — Electric plant 37,141 39,358 Total finance lease assets $ 91,045 $ 95,114 Other current liabilities $ 3,786 $ 3,371 Finance lease liabilities 96,850 99,512 Total finance lease liabilities $ 100,636 $ 102,883 Weighted Average Remaining Lease Term Operating leases 21.2 Years 21.3 Years Finance leases 16.9 Years 18.0 Years Weighted Average Discount Rate Operating leases 3.76 % 3.75 % Finance leases 3.10 % 3.08 %
Finance Lease, Liability, Maturity	The following table summarizes the Company’s estimated future minimum lease payments as of December 31, 2024: Puget Energy and Future Minimum Lease Payments (Dollars in Thousands) At December 31, Operating Leases Finance Leases 2025 $ 24,687 $ 7,097 2026 24,858 7,140 2027 24,469 7,023 2028 21,680 7,106 2029 12,622 6,964 Thereafter 153,937 96,138 Total lease payments $ 262,253 $ 131,468 Less imputed interest (72,792) (30,832) Total net present value $ 189,461 $ 100,636
Lessee, Operating Lease, Liability, Maturity	The following table summarizes the Company’s estimated future minimum lease payments as of December 31, 2024: Puget Energy and Future Minimum Lease Payments (Dollars in Thousands) At December 31, Operating Leases Finance Leases 2025 $ 24,687 $ 7,097 2026 24,858 7,140 2027 24,469 7,023 2028 21,680 7,106 2029 12,622 6,964 Thereafter 153,937 96,138 Total lease payments $ 262,253 $ 131,468 Less imputed interest (72,792) (30,832) Total net present value $ 189,461 $ 100,636

Accounting for Derivative Ins_2

Accounting for Derivative Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2024
Derivative [Line Items]
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value	The following table presents the volumes, fair values and classification of the Company's derivative instruments recorded on the balance sheets: Puget Energy and Year Ended December 31, (Dollars in Thousands) Volumes (millions) Assets 1 Liabilities² 2024 2023 2024 2023 2024 2023 Electric portfolio derivatives 3 * * $ 35,341 $ 93,028 $ 319,506 $ 126,939 Natural gas derivatives (MMBtus) 3 269 301 3,495 16,521 70,425 96,898 Total derivative contracts $ 38,836 $ 109,549 $ 389,931 $ 223,837 Current $ 32,591 $ 74,225 $ 218,443 $ 185,788 Long-term 6,245 35,324 171,488 38,049 Total derivative contracts $ 38,836 $ 109,549 $ 389,931 $ 223,837 __________ 1. Balance sheet classification: Current and Long-term Unrealized gain on derivative instruments. 2. Balance sheet classification: Current and Long-term Unrealized loss on derivative instruments. 3. All fair value adjustments on derivatives have been deferred in accordance with ASC 980, “Regulated Operations" in 2024. The net derivative asset or liability and offsetting regulatory liability or asset are related to contracts used to economically hedge the cost of electricity and physical gas purchased to serve customers. In 2023, only fair value adjustments for contracts used to serve natural gas customers were deferred. * Electric portfolio derivatives consist of electric generation fuel of 283.5 million One Million British Thermal Units (MMBtus) and purchased electricity of 13.3 million megawatt hours (MWhs) at December 31, 2024, and 315.6 million MMBtus and 2.3 million MWhs at December 31, 2023.
Offsetting Assets and Liabilities [Table Text Block]	The following tables present the potential effect of netting arrangements, including rights of set-off associated with the Company's derivative assets and liabilities: Puget Energy and December 31, 2024 (Dollars in Thousands) Gross Amount Recognized in the Consolidated Balance Sheet 1 Gross Amounts Offset in the Consolidated Balance Sheet Net of Amounts Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Commodity Contracts 2 Cash Collateral Received/Pledged Net Amount Assets: Energy derivative contracts $ 38,836 $ — $ 38,836 $ (34,329) $ — $ 4,507 Liabilities: Energy derivative contracts $ 389,931 $ — $ 389,931 $ (34,329) $ (3,593) $ 352,009 Puget Energy and December 31, 2023 (Dollars in Thousands) Gross Amount Recognized 1 Gross Amounts Offset in the Consolidated Balance Sheet Net of Amounts Presented in the Consolidated Balance Sheet Gross Amounts Not Offset in the Consolidated Balance Sheet Commodity Contracts 2 Cash Collateral Received/Pledged Net Amount Assets Energy derivative contracts $ 109,549 $ — $ 109,549 $ (82,206) $ — $ 27,343 Liabilities Energy derivative contracts $ 223,837 $ — $ 223,837 $ (82,206) $ (84) $ 141,547 __________ 1. All derivative contract deals are executed under ISDA, NAESB, and WSPP master agreements with right of set-off. 2. Amounts reflect netting by Counterparty and right of set-off.
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block]	The following table presents the effect and locations of the realized and unrealized gains (losses) of the Company's derivatives recorded on the statements of income: Puget Energy and Year Ended December 31, (Dollars in Thousands) Location 2024 2023 2022 Gas for Power Derivatives: Unrealized Unrealized gain (loss) on derivative instruments, net $ 53,541 $ (155,774) $ 61,761 Realized Electric generation fuel (85,476) 47,930 158,550 Power Derivatives: Unrealized Unrealized gain (loss) on derivative instruments, net (19,630) (128,721) 199,416 Realized Purchased electricity (76,271) 69,136 20,917 Total gain (loss) recognized in income on derivatives $ (127,836) $ (167,429) $ 440,644
Schedule of Credit Risk Related Contingent Features [Table Text Block]	The following table presents the aggregate fair value of all derivative instruments with credit-risk-related contingent features that are in a liability position and the amount of additional collateral the Company could be required to post: Puget Energy and December 31, (Dollars in Thousands) 2024 2023 Contingent Feature Fair Value 1 Liability Posted Contingent Fair Value 1 Liability Posted Contingent Credit rating 2 $ 179,532 $ — $ 179,532 $ 13,384 $ — $ 13,384 Requested credit for adequate assurance 37,492 — — 53,427 — — Forward value of contract 3 19,905 12,915 N/A 84 12,429 N/A Total $ 236,929 $ 12,915 $ 179,532 $ 66,895 $ 12,429 $ 13,384 _______________ 1. Represents the derivative fair value of contracts with contingent features for counterparties in net derivative liability positions. Excludes NPNS, accounts payable and accounts receivable. 2. Failure by PSE to maintain an investment grade credit rating from each of the major credit rating agencies provides counterparties a contractual right to demand collateral. 3. Collateral requirements may vary, based on changes in the forward value of underlying transactions relative to contractually defined collateral thresholds.

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Inputs, Liabilities, Quantitative Information	The carrying values and estimated fair values were as follows: Puget Energy December 31, 2024 December 31, 2023 (Dollars in Thousands) Level Carrying Value Fair Value Carrying Value Fair Value Financial liabilities: Long-term debt (fixed-rate), net of discount 1 2 $ 7,423,919 $ 6,966,211 $ 7,036,642 $ 6,855,503 Total $ 7,423,919 $ 6,966,211 $ 7,036,642 $ 6,855,503 Puget Sound Energy December 31, 2024 December 31, 2023 (Dollars in Thousands) Level Carrying Value Fair Value Carrying Value Fair Value Financial liabilities: Long-term debt (fixed-rate), net of discount 2 2 $ 5,961,025 $ 5,492,999 $ 5,184,047 $ 5,007,483 Total $ 5,961,025 $ 5,492,999 $ 5,184,047 $ 5,007,483 _______________ 1. The carrying value includes debt issuances costs of $21.3 million and $21.0 million for December 31, 2024, and 2023, respectively, which are not included in fair value. 2. The carrying value includes debt issuances costs of $22.1 million and $21.2 million for December 31, 2024, and 2023, respectively, which are not included in fair value.
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]	Puget Energy and Year Ended December 31, Level 3 Roll-Forward Net Asset (Liability) 2024 2023 2022 (Dollars in Thousands) Electric Natural Gas Total Electric Natural Gas Total Electric Natural Gas Total Balance at beginning of period $ 27,262 $ 3,851 $ 31,113 $ 116,078 $ (127) $ 115,951 $ (42,752) $ (2,120) $ (44,872) Changes during period: Realized and unrealized energy derivatives Included in earnings 1 (27,262) — (27,262) (56,656) — (56,656) 180,533 — 180,533 Included in regulatory assets / liabilities (211,129) 1,284 (209,845) — 4,906 4,906 — 301 301 Settlements 2 34,873 (4,418) 30,455 (32,377) (1,098) (33,475) (21,972) 1,369 (20,603) Transferred into Level 3 — — — — — — — — — Transferred out Level 3 1,146 674 1,820 217 170 387 269 323 592 Balance at end of period $ (175,110) $ 1,391 $ (173,719) $ 27,262 $ 3,851 $ 31,113 $ 116,078 $ (127) $ 115,951 __________________ 1. Income Statement classification: Unrealized gain (loss) on derivative instruments, net. Includes unrealized gains (losses) on derivatives still held in position as of the reporting date for electric derivatives of $(17.3) million and $147.1 million for the years ended December 31, 2023, and 2022, respectively. 2. The Company had no purchases or sales of options during the reported periods.
Fair Value Inputs, Assets and Liabilities, Quantitative Information [Table Text Block]	Below are the forward price ranges for the Company's commodity contracts, as of December 31, 2024: Puget Energy and Fair Value Range (Dollars in Thousands) Assets 1 Liabilities 1 Valuation Technique Unobservable Input Low High Weighted Electricity $ 10,104 $ 185,214 Discounted cash flow Power Prices (per MWh) $ 13.82 $ 138.94 $ 64.59 Natural Gas $ 1,767 $ 376 Discounted cash flow Natural Gas Prices (per MMBtu) $ 2.66 $ 4.17 $ 3.66 _______________ 1 The valuation techniques, unobservable inputs and ranges are the same for asset and liability positions.
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following tables present the Company's financial assets and liabilities by level, within the fair value hierarchy, that were accounted for at fair value on a recurring basis and the reconciliation of the changes in the fair value of Level 3 derivatives in the fair value hierarchy: Puget Energy and Fair Value Fair Value December 31, 2024 December 31, 2023 (Dollars in Thousands) Level 2 Level 3 Total Level 2 Level 3 Total Assets: Electric derivative instruments $ 25,236 $ 10,105 $ 35,341 $ 42,254 $ 50,774 $ 93,028 Gas derivative instruments 1,729 1,766 3,495 11,647 4,874 16,521 Total derivative assets $ 26,965 $ 11,871 $ 38,836 $ 53,901 $ 55,648 $ 109,549 Liabilities: Electric derivative instruments $ 134,292 $ 185,214 $ 319,506 $ 103,427 $ 23,512 $ 126,939 Gas derivative instruments 70,050 375 70,425 95,875 1,023 96,898 Compliance obligation 73,049 — 73,049 168,879 — 168,879 Total derivative liabilities $ 277,391 $ 185,589 $ 462,980 $ 368,181 $ 24,535 $ 392,716

Retirement Benefits (Tables)

Retirement Benefits (Tables)	12 Months Ended
	Dec. 31, 2024
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Changes in Projected Benefit Obligations	The following tables summarize the Company’s change in benefit obligation, change in plan assets and amounts recognized in the Statements of Financial Position for the years ended December 31, 2024, and 2023: Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Change in benefit obligation: Benefit obligation at beginning of period $ 609,103 $ 589,278 $ 26,824 $ 32,046 $ 8,597 $ 9,015 Amendments — — — — 34 78 Service cost 18,616 18,530 — 143 197 184 Interest cost 31,152 32,375 1,370 1,589 406 439 Curtailment loss / (gain) — — — (2,772) — — Actuarial loss (gain) (38,952) 8,469 (1,752) (661) (194) (52) Benefits paid (41,583) (38,258) (1,978) (3,521) (792) (1,067) Administrative expense (1,350) (1,291) — — — — Benefit obligation at end of period* $ 576,986 $ 609,103 $ 24,464 $ 26,824 $ 8,248 $ 8,597 • The amount is the actuarial present value of the vested benefits to which the employee is currently entitled and is based on the employee's expected date of separation or retirement.
Schedule of Changes in Fair Value of Plan Assets	Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Change in plan assets: Fair value of plan assets at beginning of period $ 746,011 $ 658,533 $ — $ — $ 5,085 $ 5,190 Actual return on plan assets 51,509 109,028 — — 313 543 Employer contribution 18,000 18,000 1,978 3,521 179 419 Benefits paid (41,583) (38,258) (1,978) (3,521) (792) (1,067) Administrative expense (1,247) (1,292) — — — — Fair value of plan assets at end of period $ 772,690 $ 746,011 $ — $ — $ 4,785 $ 5,085 Funded status at end of period $ 195,704 $ 136,908 $ (24,464) $ (26,824) $ (3,463) $ (3,512)
Schedule of Net Benefit Costs	The following tables summarize Puget Energy's and PSE's net periodic benefit cost for the years ended December 31, 2024, 2023, and 2022. Puget Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2022 2024 2023 2022 2024 2023 2022 Components of net periodic benefit cost: Service cost $ 18,616 $ 18,530 $ 26,351 $ — $ 143 $ 557 $ 197 $ 184 $ 217 Interest cost 31,152 32,375 24,263 1,370 1,589 1,253 406 439 311 Expected return on plan assets (54,896) (50,641) (51,014) — — — (288) (297) (379) Amortization of prior service cost (credit) — — — — 144 289 33 28 22 Amortization of net loss (gain) (2,684) (2,447) 6,381 (42) — 2,471 (139) (210) (29) Net periodic benefit cost $ (7,812) $ (2,183) $ 5,981 $ 1,328 $ 1,876 $ 4,570 $ 209 $ 144 $ 142
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)	The following tables summarize Puget Energy's and PSE's benefit obligations recognized in other comprehensive income (OCI) for the years ended December 31, 2024, and 2023: Puget Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Other changes (pre-tax) in plan assets and benefit obligations recognized in other comprehensive income: Net loss (gain) $ (44,439) $ (49,917) $ (1,751) $ (3,433) $ (219) $ (298) Amortization of net (loss) gain 2,684 2,447 42 — 139 210 Settlements, mergers, sales, and closures — — — (145) — — Prior service cost (credit) — — — — 34 79 Amortization of prior service (cost) credit — — — (144) (33) (28) Total change in other comprehensive income for year $ (41,755) $ (47,470) $ (1,709) $ (3,722) $ (79) $ (37)
Schedule of Assumptions Used	In accounting for pension and other benefit obligations and costs under the plans, the following weighted-average actuarial assumptions were used by the Company: Qualified SERP Other Benefit Obligation Assumptions: 2024 2023 2022 2024 2023 2022 2024 2023 2022 Discount rate 5.80 % 5.30 % 5.60 % 5.80 % 5.30 % 5.60 % 5.80 % 5.30 % 5.60 % Rate of compensation increase 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 Interest crediting rate 4.00 4.00 4.00 N/A N/A N/A N/A N/A N/A Benefit Cost Assumptions: Discount rate 5.30 5.60 3.00 5.30 5.60 3.00 5.30 5.60 3.00 Return on plan assets 7.00 6.75 6.50 — — — 7.00 7.00 7.00 Rate of compensation increase 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 4.50 Interest crediting rate 4.00 4.00 4.00 N/A N/A N/A N/A N/A N/A
Schedule of Expected Benefit Payments	The expected total benefits to be paid during the next five years and the aggregate total to be paid for the five years thereafter are as follows: (Dollars in Thousands) 2025 2026 2027 2028 2029 2030-2034 Qualified Pension total benefits $ 43,800 $ 44,700 $ 45,400 $ 46,100 $ 47,100 $ 242,200 SERP Pension total benefits 6,759 2,263 4,222 1,630 1,559 7,295 Other Benefits total 870 847 838 834 837 3,491
Schedule of Allocation of Plan Assets	To obtain the desired return needed to fund the pension benefit plans, the Retirement Plan Committee has established investment allocation percentages by asset classes as follows: Allocation Asset Class Minimum Target Maximum Domestic large cap equity 22 % 28 % 35 % Domestic small cap equity — 8 12 Non-U.S. equity 10 24 30 Fixed income 30 40 50 Cash — — 5 The following table sets forth by level, within the fair value hierarchy, the qualified pension plan as of December 31, 2024, and 2023: Recurring Fair Value Measures Recurring Fair Value Measures December 31, 2024 December 31, 2023 (Dollars in Thousands) Level 1 Level 2 Other Total Level 1 Level 2 Other Total Assets: Common Stock: Domestic $ 117,183 $ 199 $ — $ 117,382 $ 130,288 $ 281 $ — $ 130,569 Foreign 14,050 — — 14,050 13,767 — — 13,767 Government Securities 100,126 13,172 — 113,298 73,243 12,709 — 85,952 Corporate Securities: Domestic — 17,807 — 17,807 — 14,787 — 14,787 Foreign — 15,004 — 15,004 — 8,829 — 8,829 Mutual Funds 75,186 — — 75,186 81,130 — — 81,130 Cash and cash equivalents 5,263 (6,323) — (1,060) 2,846 236 — 3,082 Investments measured at NAV: Collective Investment Funds — — 321,937 321,937 — — 297,780 297,780 Partnership — — 90,308 90,308 — — 91,845 91,845 Mutual Funds — — 57,187 57,187 — — 48,116 48,116 Other — — 2,045 2,045 — — 128 128 Net (payable) receivable — — (50,454) (50,454) — — (29,974) (29,974) Total assets $ 311,808 $ 39,859 $ 421,023 $ 772,690 $ 301,274 $ 36,842 $ 407,895 $ 746,011
Defined Benefit Plan, Plan with Accumulated Benefit Obligation in Excess of Plan Assets [Table Text Block]	Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Change in plan obligation and plan asset: Projected benefit obligation $ 576,986 $ 609,103 $ 24,464 $ 26,824 $ 8,248 $ 8,597 Accumulated benefit obligation 571,306 601,981 24,464 26,824 8,109 8,487 Fair value of plan assets 772,690 746,011 — — 4,785 5,085
Schedule of Amounts Recognized in Accumulated Other Comprehensive Income	The following tables summarize Puget Energy's and PSE's pension benefit amounts recognized in accumulated other comprehensive income (AOCI) for the years ended December 31, 2024, and 2023: Puget Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Amounts recognized in Accumulated Other Comprehensive Income consist of: Net loss (gain) $ (49,242) $ (16,257) $ (3,579) $ (1,870) $ (2,132) $ (2,052) Prior service cost (credit) — — — — 311 310 Total $ (49,242) $ (16,257) $ (3,579) $ (1,870) $ (1,821) $ (1,742) Puget Sound Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Amounts recognized in Accumulated Other Comprehensive Income consist of: Net loss (gain) $ 39,183 $ 74,851 $ (3,342) $ (1,613) $ (2,204) $ (2,124) Prior service cost (credit) — — — — 311 310 Total $ 39,183 $ 74,851 $ (3,342) $ (1,613) $ (1,893) $ (1,814)
Schedule of Amounts Recognized in Balance Sheet	Puget Energy and Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Amounts recognized in Consolidated Balance Sheet consist of: Noncurrent assets $ 195,704 $ 136,908 $ — $ — $ — $ — Current liabilities — — (6,759) (1,978) (237) (225) Noncurrent liabilities — — (17,705) (24,846) (3,226) (3,287) Net assets (liabilities) $ 195,704 $ 136,908 $ (24,464) $ (26,824) $ (3,463) $ (3,512)
Other Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Allocation of Plan Assets	The following table sets forth by level, within the fair value hierarchy, the Other Benefits plan assets which consist of insurance benefits for retired employees, at fair value: Recurring Fair Value Measures Recurring Fair Value Measures December 31, 2024 December 31, 2023 (Dollars in Thousands) Level 1 Level 2 Other Total Level 1 Level 2 Other Total Assets: Mutual fund $ — $ 4,785 $ — $ 4,785 $ — $ 5,085 $ — $ 5,085 Total assets $ — $ 4,785 $ — $ 4,785 $ — $ 5,085 $ — $ 5,085 The following discussion provides information regarding the methods used in valuation of the various asset class investments held for the pension and other postretirement benefit plans. • Mutual funds classified as Level 1 securities have pricing inputs that are based on quoted prices in an active market. Principal markets for equity prices include published exchanges such as NASDAQ and New York Stock Exchange (NYSE). Mutual fund assets not included in the fair value hierarchy are privately held funds. These funds are not actively traded and utilize net asset value (NAV) as a practical expedient to measure fair value. • Common stock investments are traded in active markets on national and international securities exchanges and are valued at closing prices on the last business day of each period presented. They are classified as Level 1 securities. • Corporate and some government debt securities are valued using pricing models maximizing the use of observable inputs for similar securities. This includes basing value on yields currently available on comparable securities of issuers with similar credit ratings. Some government debt securities have quoted prices such as certain treasury securities and are classified as Level 1 securities. • Cash and cash equivalents comprise mostly of money market funds and foreign currency held. Money market funds are classified as Level 1 instruments as pricing inputs are based on unadjusted prices in an active market while foreign currency held is classified as a Level 2 investment based on inputs that are indirectly observable. • Investments in collective trust funds and partnerships are stated at the NAV as determined by the issuer of the fund and are based on the fair value of the underlying investments held by the fund less its liabilities. The NAV is used as a practical expedient to estimate fair value. These funds are primarily invested in a blend of corporate and government debt securities as well as international equities.
Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Net Benefit Costs	Puget Sound Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2022 2024 2023 2022 2024 2023 2022 Components of net periodic benefit cost: Service cost $ 18,616 $ 18,530 $ 26,351 $ — $ 143 $ 557 $ 197 $ 184 $ 217 Interest cost 31,152 32,375 24,263 1,370 1,589 1,253 406 439 311 Expected return on plan assets (54,897) (50,641) (51,016) — — — (288) (297) (379) Amortization of prior service cost (credit) — — — — 144 289 33 28 22 Amortization of net loss (gain) — — 15,080 (22) 44 2,648 (139) (230) (35) Net periodic benefit cost $ (5,129) $ 264 $ 14,678 $ 1,348 $ 1,920 $ 4,747 $ 209 $ 124 $ 136
Schedule of Amounts Recognized in Other Comprehensive Income (Loss)	Puget Sound Energy Qualified SERP Other (Dollars in Thousands) 2024 2023 2024 2023 2024 2023 Other changes (pre-tax) in plan assets and benefit obligations recognized in other comprehensive income: Net loss (gain) $ (44,438) $ (49,916) $ (1,751) $ (3,433) $ (219) $ (298) Amortization of net (loss) gain — — 22 (44) 139 230 Settlements, mergers, sales, and closures — — — (145) — — Prior service cost (credit) — — — — 34 79 Amortization of prior service (cost) credit — — — (144) (33) (28) Total change in other comprehensive income for year $ (44,438) $ (49,916) $ (1,729) $ (3,766) $ (79) $ (17)

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2024
Income Tax Disclosures [Line Items]
Schedule of Components of Income Tax Expense (Benefit)	The details of income tax (benefit) expense are as follows: Puget Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Charged to operating expenses: Current: Federal $ 31,101 $ 66,086 $ 41,198 State 364 1,317 628 Deferred: Federal (875) (94,860) 17,866 State 133 23 6 Total income tax expense $ 30,723 $ (27,434) $ 59,698
Schedule of Effective Income Tax Rate Reconciliation	The following reconciliation compares pre-tax book income at the federal statutory rate of 21.0% to the actual income tax expense in the Consolidated Statements of Income: Puget Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Income taxes at the statutory rate $ 63,256 21.0 % $ 5,524 21.0 % $ 99,549 21.0 % Increase (decrease): Utility plant differences 1 $ (29,712) (9.9) % $ (23,806) (90.5) % $ (23,028) (4.9) % AFUDC, net (5,704) (1.9) (4,017) (15.3) (3,567) (0.8) % Executive compensation 2,209 0.7 1,544 5.9 1,821 0.4 % Treasury grant amortization (797) (0.3) (750) (2.9) (5,717) (1.2) % Excess deferred tax amortization — — (8,689) (33.0) (13,722) (2.9) % State taxes, net 393 0.1 1,070 4.1 505 0.1 % Other–net 1,078 0.4 1,690 6.4 3,857 0.9 % Total income tax expense $ 30,723 10.1 % $ (27,434) (104.3) % $ 59,698 12.6 % Puget Sound Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Income taxes at the statutory rate $ 84,835 21.0 % $ 26,136 21.0 % $ 119,962 21.0 % Increase (decrease): Utility plant differences 1 $ (29,712) (7.4) % $ (23,806) (19.1) % $ (23,028) (4.0) % AFUDC, net (5,704) (1.4) % (4,017) (3.2) % (3,567) (0.6) % Excess deferred tax amortization — — % (8,689) (7.0) % (13,722) (2.4) % State taxes, net 702 0.2 % 1,291 1.0 % 689 0.1 % Other–net 2,466 0.6 % 2,482 2.0 % (39) — % Total income tax expense $ 52,587 13.0 % $ (6,603) (5.3) % $ 80,295 14.1 % _______________ 1. Utility plant differences include the reversal of excess deferred taxes using the average rate assumption method in the amount of $29.8 million, $27.8 million and $27.2 million in 2024, 2023 and 2022, respectively.
Schedule of Deferred Tax Assets and Liabilities	The Company’s net deferred tax liability at December 31, 2024, and 2023, is composed of amounts related to the following types of temporary differences: Puget Energy At December 31, (Dollars in Thousands) 2024 2023 Utility plant and equipment $ 1,768,358 $ 1,799,505 Other deferred tax liabilities 466,317 407,842 Subtotal deferred tax liabilities 2,234,675 2,207,347 Net operating loss carryforward (201,562) (210,238) Net regulatory liability for income taxes (721,907) (760,961) Other deferred tax assets (313,526) (285,919) Subtotal deferred tax assets (1,236,995) (1,257,118) Total net deferred tax liabilities $ 997,680 $ 950,229 Puget Sound Energy At December 31, (Dollars in Thousands) 2024 2023 Utility plant and equipment $ 1,763,456 $ 1,796,476 Other deferred tax liabilities 382,968 319,328 Subtotal deferred tax liabilities 2,146,424 2,115,804 Net regulatory liability for income taxes (722,558) (761,621) Other deferred tax assets (306,374) (275,336) Subtotal deferred tax assets (1,028,932) (1,036,957) Total net deferred tax liabilities $ 1,117,492 $ 1,078,847
Subsidiaries [Member]
Income Tax Disclosures [Line Items]
Schedule of Components of Income Tax Expense (Benefit)	Puget Sound Energy Year Ended December 31, (Dollars in Thousands) 2024 2023 2022 Charged to operating expenses: Current: Federal $ 61,924 $ 112,168 $ 81,597 State 889 1,626 869 Deferred: Federal (10,226) (120,397) (2,171) State — — — Total income tax expense $ 52,587 $ (6,603) $ 80,295

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2024
Long-term Purchase Commitment [Line Items]
Schedule of Long-term Contracts for Purchase of Electric Power	The Company's expenses under these PUD contracts were as follows for the years ended December 31: (Dollars in Thousands) 2024 2023 2022 PUD contract costs $ 211,800 $ 174,385 $ 149,575 As of December 31, 2024, the Company purchased portions of the power output of the PUDs' projects as set forth in the following table: Company's Share of (Dollars in Thousands) Contract 2025 Percent of Output 2025 Megawatt Capacity Estimated 2025 Total Costs 2025 Debt Service Costs Interest included in 2025 Debt Service Costs Debt Outstanding Chelan County PUD 1 : Rock Island Project 2051 40.0 % 252 $ 85,641 $ 20,499 $ 5,572 $ 98,638 Rocky Reach Project 2051 40.0 540 112,077 6,166 1,808 32,155 Douglas County PUD 2 : Wells Project 2032 18.6 156 42,883 — — — Grant County PUD 3 : Priest Rapids Development 2052 9.9 94 54,717 310 166 4,112 Wanapum Development 2052 9.9 121 54,717 310 166 4,112 Total 1,163 $ 350,035 $ 27,285 $ 7,712 $ 139,017 _______________ 1. PSE currently purchases output from Chelan County PUD's Rock Island and Rocky Reach hydroelectric projects under four separate contracts: 1) a contract for 25% of output that was executed in February 2006 and expires October 31, 2031. In 2023, PSE executed a new contract extending this 25% share of output through October 2051; 2) a contract executed in March 2021 for 5% of output that began on January 1, 2022 and continues through December 31, 2026; 3) a contract executed during 2023 to purchase an additional 5% of output for each from January 1, 2024 through December 31, 2028; and 4) a contract executed during 2024 to purchase an additional 5% of output that begins on February 1, 2025 and continues through December 31, 2025. 2. PSE currently purchases output from Douglas County PUD's Wells hydroelectric project under three separate contracts: 1) a contract executed in March 2017 with a variable share output (average 13.1% in 2025) that began on September 1, 2018 and ends September 30, 2028; 2) a contract executed in March 2021 for 5.5% of output from October 1, 2021 through September 30, 2024. In 2023, PSE executed a new contract extending this 5.5% share of output through September 30, 2029; and 3) a contract executed in August 2024 for 9.5% to 18.9% share of output from January 1, 2026 through December 31, 2032. 3. PSE currently purchases output from Grant County PUD's Wanapum and Priest Rapids hydroelectric developments under four separate contracts: 1) a contract that was executed on December 13, 2001 and began November 1, 2005 under which PSE receives 0.64% of output through March 31, 2052; 2) a contract entered in June 2024 for 4.22% of output from the Annual Auction that begins on January 1, 2025, and continues through December 31, 2025; 3) a contract entered in April 2024 for 0.88% of output from the Eugene Water and Electric Board Meaningful Priority rights that begins on January 1, 2025, and continues through December 31, 2025 ; and 4) a contract entered in April 2024 for 4.13% of output from the Meaningful Priority rights that begins on January 1, 2025, and continues through December 31, 2025. PSE reserves the right to renew the latter contract on an annual basis.
Schedule of Long-term Purchase Commitments	The following table summarizes the Company’s estimated obligations for energy production service contracts through the terms of its existing contracts. Service Contract Obligations 2025 2026 2027 2028 2029 Thereafter Total Energy production service contracts $ 36,920 $ 40,184 $ 40,987 $ 41,823 $ 42,639 $ 60,494 $ 263,047
Electricity, Purchased [Member]
Long-term Purchase Commitment [Line Items]
Schedule of Long-term Purchase Commitments	The following table summarizes the Company’s estimated payment obligations for purchases from electric portfolio contracts and electric wholesale market transactions. These contracts have varying terms and may include escalation and termination provisions. (Dollars in Thousands) 2025 2026 2027 2028 2029 Thereafter Total Columbia River projects $ 350,035 $ 238,243 $ 226,541 $ 238,331 $ 171,203 $ 3,563,272 $ 4,787,625 Electric portfolio contracts 474,683 255,973 258,701 304,056 291,040 3,709,279 5,293,732 Electric wholesale market transactions 226,141 157,991 87,434 57,019 56,982 515,240 1,100,807 Total $ 1,050,859 $ 652,207 $ 572,676 $ 599,406 $ 519,225 $ 7,787,791 $ 11,182,164
Natural Gas, US Regulated [Member]
Long-term Purchase Commitment [Line Items]
Schedule of Long-term Purchase Commitments	The following table summarizes the Company’s obligations for future natural gas supply and demand charges through the primary terms of its existing contracts. The quantified obligations are based on the FERC and Canadian Energy Regulator (CER) currently authorized rates, which are subject to change. Natural Gas Supply and Demand Charge Obligations 2025 2026 2027 2028 2029 Thereafter Total Natural gas wholesale market transactions $ 517,802 $ 429,749 $ 277,306 $ 180,565 $ 79,714 $ — $ 1,485,136 Firm transportation service 167,274 165,151 166,716 163,261 144,884 669,602 1,476,888 Firm storage service 9,350 8,476 8,189 2,678 837 4,946 34,476 Total $ 694,426 $ 603,376 $ 452,211 $ 346,504 $ 225,435 $ 674,548 $ 2,996,500

Accumulated Other Comprehensi_2

Accumulated Other Comprehensive Income (Loss) (Tables)	12 Months Ended
	Dec. 31, 2024
Accumulated Other Comprehensive Income (Loss) [Line Items]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	The following tables present the changes in the Company’s (loss) AOCI by component for the years ended December 31, 2024, 2023 and 2022, respectively: Puget Energy Net unrealized gain (loss) and prior service cost on pension plans Changes in AOCI, net of tax (Dollars in Thousands) Total Balance at December 31, 2021 $ (27,432) $ (27,432) Other comprehensive income (loss) before reclassifications (4,559) (4,559) Amounts reclassified from accumulated other comprehensive income (loss), net of tax 7,217 7,217 Net current-period other comprehensive income (loss) 2,658 2,658 Balance at December 31, 2022 $ (24,774) $ (24,774) Other comprehensive income (loss) before reclassifications 44,277 44,277 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (1,964) (1,964) Net current-period other comprehensive income (loss) 42,313 42,313 Balance at December 31, 2023 $ 17,539 $ 17,539 Other comprehensive income (loss) before reclassifications 27,866 27,866 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (2,237) (2,237) Net current-period other comprehensive income (loss) 25,629 25,629 Balance at December 31, 2024 $ 43,168 $ 43,168
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	Details about the reclassifications out of AOCI (loss) for the years ended December 31, 2024, 2023 and 2022, respectively, are as follows: Puget Energy (Dollars in Thousands) Details about accumulated other comprehensive income (loss) components Affected line item in the statement where net income (loss) is presented Amount reclassified from accumulated 2024 2023 2022 Net unrealized gain (loss) and prior service cost on pension plans: Amortization of prior service cost (a) $ (33) $ (172) $ (311) Amortization of net gain (loss) (a) 2,865 2,658 (8,824) Total before tax 2,832 2,486 (9,135) Tax (expense) or benefit (595) (522) 1,918 Net of tax 2,237 1,964 (7,217) Total reclassification for the period Net of tax $ 2,237 $ 1,964 $ (7,217) __________ (a) These AOCI components are included in the computation of net periodic pension cost, see Note 13, "Retirement Benefits," to the consolidated financial statements included in this Item 8 of this report for additional details.
Subsidiaries [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Puget Sound Energy Net unrealized gain (loss) and prior service cost on pension plans Net unrealized gain (loss) on treasury interest rate swaps Changes in AOCI, net of tax (Dollars in Thousands) Total Balance at December 31, 2021 $ (108,541) $ (4,600) $ (113,141) Other comprehensive income (loss) before reclassifications (4,512) — (4,512) Amounts reclassified from accumulated other comprehensive income (loss), net of tax 14,223 386 14,609 Net current-period other comprehensive income (loss) 9,711 386 10,097 Balance at December 31, 2022 $ (98,830) $ (4,214) $ (103,044) Other comprehensive income (loss) before reclassifications 44,277 — 44,277 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (12) 385 373 Net current-period other comprehensive income (loss) 44,265 385 44,650 Balance at December 31, 2023 $ (54,565) $ (3,829) $ (58,394) Other comprehensive income (loss) before reclassifications 27,862 — 27,862 Amounts reclassified from accumulated other comprehensive income (loss), net of tax (101) 386 285 Net current-period other comprehensive income (loss) 27,761 386 28,147 Balance at December 31, 2024 $ (26,804) $ (3,443) $ (30,247)
Reclassification out of Accumulated Other Comprehensive Income [Table Text Block]	Puget Sound Energy (Dollars in Thousands) Details about accumulated other comprehensive income (loss) components Affected line item in the statement where net income (loss) is presented Amount reclassified from accumulated 2024 2023 2022 Net unrealized gain (loss) and prior service cost on pension plans: Amortization of prior service cost (a) $ (33) $ (172) $ (311) Amortization of net gain (loss) (a) 161 187 (17,693) Total before tax 128 15 (18,004) Tax (expense) or benefit (27) (3) 3,781 Net of tax 101 12 (14,223) Net unrealized gain (loss) on treasury interest rate swaps: Interest rate contracts Interest expense (487) (488) (488) Tax (expense) or benefit 101 103 102 Net of tax (386) (385) (386) Total reclassification for the period Net of tax $ (285) $ (373) $ (14,609) ____________ (a) These AOCI components are included in the computation of net periodic pension cost, see Note 13, "Retirement Benefits," to the consolidated financial statements included in this Item 8 of this report for additional details.

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2024
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	The chief operating decision maker uses net income by comparing actual results to budget to assess Company performance. Puget Energy Year Ended December 31, 2024 (Dollars in Thousands) Regulated Utility Other Total Revenue $ 4,825,231 $ 30,984 $ 4,856,215 Depreciation and amortization 781,325 6,661 787,986 Income tax (benefit) expense 52,587 (21,864) 30,723 Non-utility expense and other 21,664 24,392 46,056 Interest expense (321,550) (110,644) (432,194) Net income 346,148 (80,893) 265,255 Total assets 17,026,384 1,934,007 18,960,391 Construction expenditures (1,608,947) (768) (1,609,715) Puget Energy Year Ended December 31, 2023 (Dollars in Thousands) Regulated Utility Other Total Revenue $ 4,786,618 $ 29,956 $ 4,816,574 Depreciation and amortization 744,629 6,706 751,335 Income tax (benefit) expense (6,603) (20,831) (27,434) Non-utility expense and other 28,658 27,857 56,515 Interest expense (285,148) (96,363) (381,511) Net income 131,059 (77,319) 53,740 Total assets 15,771,767 1,960,686 17,732,453 Construction expenditures (1,465,925) (640) (1,466,565) Puget Energy Year Ended December 31, 2022 (Dollars in Thousands) Regulated Utility Other Total Revenue $ 4,216,173 $ 4,989 $ 4,221,162 Depreciation & Amortization 657,349 5,883 663,232 Income Tax (Benefit) Expense 80,295 (20,597) 59,698 Non-utility expense and other 47,194 12,610 59,804 Interest expense (256,774) (91,147) (347,921) Net Income 490,952 (76,607) 414,345 Total assets 15,200,242 1,987,272 17,187,514 Construction expenditures (1,000,810) (3,903) (1,004,713)

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Details)				12 Months Ended
	Feb. 03, 2021	May 28, 2020	Apr. 12, 2017	Dec. 31, 2024 USD ($) mi² segment	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jan. 01, 2026 USD ($)	Jan. 01, 2025 USD ($)	Jan. 01, 2018 USD ($)
Accounting Policies
Allowance for doubtful accounts				$ 40,436,000	$ 38,211,000
Bad Debt Deferral, COVID 19				37,100,000	17,100,000
Excise and Sales Taxes				329,900,000	319,100,000	$ 292,800,000
Related Party Transaction, Amounts of Transaction				$ 0	0	0
Number of operating segments | segment				1
Unrealized gain on derivative instruments				$ 32,591,000	74,225,000
Derivative Asset				38,800,000
Derivative Liability				389,900,000
Unrealized loss on derivative instruments				33,911,000	$ (284,495,000)	$ 261,177,000
Unrealized Gain (Loss) on Derivatives Deferred				$ 351,100,000
Common Plant
Accounting Policies
Annual depreciation provision				6.60%	6.50%	7.10%
Electricity, US Regulated [Member]
Accounting Policies
Annual depreciation provision				3.40%	3.40%	3.40%
Natural Gas, US Regulated [Member]
Accounting Policies
Annual depreciation provision				3.20%	3.20%	2.90%
Subsidiaries [Member]
Accounting Policies
Area of service territory (sqmi) | mi²				6,000
Allowance for doubtful accounts				$ 40,436,000	$ 38,211,000
Public Utilities, Rate Case, Deferred Storm Costs Threshold				$ 10,000,000					$ 10,000,000
Regulatory Asset, Amortization Period				1 year
Regulatory Liability, Amortization Period				1 year
Public Utilities, Rate Case, Deferred Storm Qualifying Costs				$ 500,000
Unrealized gain on derivative instruments				32,591,000	74,225,000
Unrealized loss on derivative instruments				33,911,000	(284,495,000)	$ 261,177,000
Variable Interest Entity [Line Items]
Variable Interest Entity, Payable				11,600,000	14,600,000
Variable Interest Entity, Measure of Activity, Purchases				$ 88,900,000	86,000,000	38,600,000
Subsidiaries [Member] | Forecast
Accounting Policies
Public Utilities, Rate Case, Deferred Storm Costs Threshold							$ 9,600,000	$ 9,400,000
Subsidiaries [Member] | Clearwater Wind Project
Accounting Policies
Contract Length, PPA	25 years
Subsidiaries [Member] | Golden Hills Wind Farm
Accounting Policies
Contract Length, PPA		20 years
Subsidiaries [Member] | Skookumchuck Wind Energy Project
Accounting Policies
Long-Term Purchase Commitment, Period			20 years
Subsidiaries [Member] | Decoupling Mechanism [Member] | Electricity, US Regulated [Member] | Maximum
Accounting Policies
Public Utilities, Approved Rate Increase (Decrease), Percentage				3%
Subsidiaries [Member] | Decoupling Mechanism [Member] | Natural Gas, US Regulated [Member] | Maximum
Accounting Policies
Public Utilities, Approved Rate Increase (Decrease), Percentage				5%
Puget LNG [Member]
Accounting Policies
Jointly Owned Non-Utility Plant Share				57%
Operating Costs and Expenses				$ 25,200,000	27,500,000	$ 11,600,000
Non-Utility Plant				$ 234,800,000	240,500,000
Tacoma LNG [Member]
Accounting Policies
Jointly Owned Non-Utility Plant Share				43%
Public Utilities, Property, Plant and Equipment, Plant in Service				$ 229,000,000	$ 235,600,000
Variable Interest Entity, Not Primary Beneficiary
Accounting Policies
Equity Method Investments				$ 0

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - AFUDC (Details)			12 Months Ended
	Dec. 22, 2022	Oct. 01, 2021	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024
Regulatory Assets [Line Items]
Public Utilities, Property, Plant and Equipment, Non-project Electric Utility Plant, Estimated Useful Life Average					30 years
Subsidiaries [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Allowance for Funds Used During Construction, Rate			7.99%	7.65%
Subsidiaries [Member] | General Rate Case [Member]
Regulatory Assets [Line Items]
Public Utilities, Allowance for Funds Used During Construction, Rate	7.16%	7.39%
Subsidiaries [Member] | General Rate Case [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Allowance for Funds Used During Construction, Rate			7.64%	7.52%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Allowance for Credit Losses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Allowance for Credit Losses, Beginning Balance	$ 40,436	$ 38,211	$ 41,962
Provision for Other Credit Losses		34,724
Receivables Charged-Off	(41,348)	(38,475)
Accounting Policies
Allowance for Credit Losses, Beginning Balance	$ 40,436	$ 38,211	$ 41,962

Revenue (Details)

Revenue (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Revenue from Contract with Customer, Including Assessed Tax		$ 4,852,387	$ 4,730,279	$ 4,134,805
Revenues		4,856,215	4,816,574	4,221,162
Other		34,950	47,431	50,069
Total Other Revenue		3,828	86,295	86,357
Electric		3,332,695	3,345,867	2,961,457
Natural gas		1,488,570	1,423,276	1,209,636
Other		34,950	47,431	50,069
Residential
Revenue from Contract with Customer, Including Assessed Tax		2,474,488	2,366,055	2,190,234
Commercial
Revenue from Contract with Customer, Including Assessed Tax		1,527,584	1,454,816	1,333,413
Industrial
Revenue from Contract with Customer, Including Assessed Tax		158,633	152,697	141,808
Other Retail Customer
Revenue from Contract with Customer, Including Assessed Tax		23,601	21,199	18,759
Wholesale
Revenue from Contract with Customer, Including Assessed Tax		286,364	498,251	319,380
Transmission and Transportation
Revenue from Contract with Customer, Including Assessed Tax		64,785	70,406	67,359
Miscellaneous Customer
Revenue from Contract with Customer, Including Assessed Tax		316,932	166,855	63,852
Puget LNG [Member]
Revenue, Remaining Performance Obligation, Amount		180,051
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction		19,554
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, 2025		19,454
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, 2026		19,454
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, 2027		19,454
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, 2028		19,454
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Thereafter		82,681
Natural gas		3,700	1,100	0
Remaining Contract Term, PLNG	10 years
Subsidiaries [Member]
Other		282	16,383	45,080
Electric		3,332,695	3,345,867	2,961,457
Natural gas		1,492,254	1,424,368	1,209,636
Electricity, US Regulated [Member]
Revenue from Contract with Customer, Including Assessed Tax		3,348,214	3,299,904	2,877,971
Total Other Revenue		(15,519)	45,963	83,486
Electricity, US Regulated [Member] | Residential
Revenue from Contract with Customer, Including Assessed Tax		1,677,599	1,514,149	1,381,858
Electricity, US Regulated [Member] | Commercial
Revenue from Contract with Customer, Including Assessed Tax		1,159,596	1,071,385	981,170
Electricity, US Regulated [Member] | Industrial
Revenue from Contract with Customer, Including Assessed Tax		131,869	123,548	116,712
Electricity, US Regulated [Member] | Other Retail Customer
Revenue from Contract with Customer, Including Assessed Tax		23,601	21,199	18,759
Electricity, US Regulated [Member] | Wholesale
Revenue from Contract with Customer, Including Assessed Tax		286,364	498,251	319,380
Electricity, US Regulated [Member] | Transmission and Transportation
Revenue from Contract with Customer, Including Assessed Tax		33,911	46,141	47,027
Electricity, US Regulated [Member] | Miscellaneous Customer
Revenue from Contract with Customer, Including Assessed Tax		35,274	25,231	13,065
Other Revenue From Contracts with Customers [Member]
Revenue from Contract with Customer, Including Assessed Tax		34,950	47,431	50,069
Total Other Revenue		0	0	0
Other Revenue From Contracts with Customers [Member] | Residential
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Other Revenue From Contracts with Customers [Member] | Commercial
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Other Revenue From Contracts with Customers [Member] | Industrial
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Other Revenue From Contracts with Customers [Member] | Other Retail Customer
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Other Revenue From Contracts with Customers [Member] | Wholesale
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Other Revenue From Contracts with Customers [Member] | Transmission and Transportation
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Other Revenue From Contracts with Customers [Member] | Miscellaneous Customer
Revenue from Contract with Customer, Including Assessed Tax		34,950	47,431	50,069
Other Revenue From Contracts with Customers [Member] | Puget LNG [Member] | Miscellaneous Customer
Revenue from Contract with Customer, Including Assessed Tax		34,700	31,000	5,000
Natural Gas, US Regulated [Member]
Revenue from Contract with Customer, Including Assessed Tax		1,469,223	1,382,944	1,206,765
Total Other Revenue		19,347	40,332	2,871
Natural Gas, US Regulated [Member] | Residential
Revenue from Contract with Customer, Including Assessed Tax		796,889	851,906	808,376
Natural Gas, US Regulated [Member] | Commercial
Revenue from Contract with Customer, Including Assessed Tax		367,988	383,431	352,243
Natural Gas, US Regulated [Member] | Industrial
Revenue from Contract with Customer, Including Assessed Tax		26,764	29,149	25,096
Natural Gas, US Regulated [Member] | Other Retail Customer
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Natural Gas, US Regulated [Member] | Wholesale
Revenue from Contract with Customer, Including Assessed Tax		0	0	0
Natural Gas, US Regulated [Member] | Transmission and Transportation
Revenue from Contract with Customer, Including Assessed Tax		30,874	24,265	20,332
Natural Gas, US Regulated [Member] | Miscellaneous Customer
Revenue from Contract with Customer, Including Assessed Tax		246,708	94,193	$ 718
Natural Gas, US Regulated [Member] | Subsidiaries [Member]
Deferred Emission Compliance Auction Proceeds, Passback to Customers		$ 253,000	$ 98,400

Regulation and Rates Net regula

Regulation and Rates Net regulatory assets and liabilities (Details) - USD ($)		12 Months Ended
	Apr. 30, 2024	Dec. 31, 2024	Dec. 31, 2023	Jan. 01, 2018
Regulatory Assets [Line Items]
Regulatory Assets		$ 1,421,272,000	$ 1,218,244,000
Regulatory Liabilities		1,886,750,000	1,962,424,000
Accrual for Environmental Loss Contingencies		73,000,000
Deferred income tax charge
Regulatory Assets [Line Items]
Regulatory Liabilities		$ 651,000	660,000
Regulatory liabilities related to power contracts
Regulatory Assets [Line Items]
Net Regulatory Assets, Remaining Amortization Period, Max		30 years
Net Regulatory Assets, Remaining Amortization Period, Min		3 years
Regulatory Liabilities		$ 30,566,000	46,924,000
Various other regulatory liabilities
Regulatory Assets [Line Items]
Regulatory Liabilities		1,193,000	1,264,000
Net Regulatory Asset (Liability)
Regulatory Assets [Line Items]
Net Regulatory Assets		(465,478,000)	(744,180,000)
Requlatory Assets Related to Power Contracts
Regulatory Assets [Line Items]
Regulatory Assets		$ 4,779,000	6,266,000
Net Regulatory Assets, Remaining Amortization Period, Max		30 years
Net Regulatory Assets, Remaining Amortization Period, Min		3 years
Subsidiaries [Member]
Regulatory Assets [Line Items]
Regulatory Assets		$ 1,416,493,000	1,211,978,000
Regulatory Asset, Amortization Period		1 year
Regulatory Liability, Amortization Period		1 year
Regulatory Liabilities		$ 1,855,642,000	1,914,896,000
Regulatory Liabilities Reclassified from Accumulated Depreciation		748,100,000	682,100,000
Annual Power Cost Variability, Amount	$ 98,200,000
Storm Damage Costs Incurred During Period		74,500,000	8,100,000
Public Utilities, Rate Case, Deferred Storm Costs Threshold		10,000,000		$ 10,000,000
Public Utilities, Rate Case, Deferred Storm Qualifying Costs		500,000
Subsidiaries [Member] | Over-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		123,300,000
Subsidiaries [Member] | Removal Costs
Regulatory Assets [Line Items]
Regulatory Liabilities		748,095,000	682,058,000
Subsidiaries [Member] | Deferred income tax charge
Regulatory Assets [Line Items]
Regulatory Liabilities		722,558,000	761,621,000
Subsidiaries [Member] | Repurposed production tax credits [Member]
Regulatory Assets [Line Items]
Regulatory Liabilities		110,746,000	126,482,000
Subsidiaries [Member] | Climate Commitment Act auction proceeds
Regulatory Assets [Line Items]
Regulatory Liabilities		$ 97,694,000	84,485,000
Subsidiaries [Member] | Deferred decoupling revenue, net [Member]
Regulatory Assets [Line Items]
Regulatory Liability, Amortization Period		2 years
Regulatory Liabilities		$ 63,890,000	60,664,000
Subsidiaries [Member] | PGA Liability
Regulatory Assets [Line Items]
Regulatory Asset, Amortization Period		2 years
Regulatory Liabilities		$ 58,657,000	132,082,000
Subsidiaries [Member] | Bill discount rate deferral
Regulatory Assets [Line Items]
Regulatory Liabilities		20,567,000	6,579,000
Subsidiaries [Member] | Various other regulatory liabilities
Regulatory Assets [Line Items]
Regulatory Liabilities		33,435,000	60,925,000
Subsidiaries [Member] | Liabilities, Total
Regulatory Assets [Line Items]
Regulatory Liabilities			1,914,896,000
Subsidiaries [Member] | Net Regulatory Asset (Liability)
Regulatory Assets [Line Items]
Net Regulatory Assets		(439,149,000)	(702,918,000)
Subsidiaries [Member] | PCA Unrealized Loss
Regulatory Assets [Line Items]
Regulatory Assets		284,166,000	0
Subsidiaries [Member] | Environmental remediation
Regulatory Assets [Line Items]
Regulatory Assets		180,245,000	182,697,000
Subsidiaries [Member] | Storm Costs [Member]
Regulatory Assets [Line Items]
Regulatory Assets		$ 120,431,000	95,754,000
Net Regulatory Assets, Remaining Amortization Period, Max		4 years
Net Regulatory Assets, Remaining Amortization Period, Min		1 year
Subsidiaries [Member] | Automatic meter reading
Regulatory Assets [Line Items]
Regulatory Assets		$ 98,572,000	104,159,000
Regulatory Asset, Amortization Period		19 years
Subsidiaries [Member] | Energy Conservation Costs [Member]
Regulatory Assets [Line Items]
Regulatory Assets		$ 75,373,000	37,560,000
Subsidiaries [Member] | PGA unrealized loss
Regulatory Assets [Line Items]
Regulatory Assets		66,929,000	80,376,000
Subsidiaries [Member] | PCA Mechanism [Member]
Regulatory Assets [Line Items]
Regulatory Assets		61,202,000	48,427,000
Subsidiaries [Member] | Baker Dam Licensing Operating Maintenance Costs [Member]
Regulatory Assets [Line Items]
Regulatory Assets		$ 56,201,000	55,641,000
Hydro license term		50 years
Subsidiaries [Member] | Deferred Washington Commission AFUDC
Regulatory Assets [Line Items]
Regulatory Assets		$ 55,427,000	58,648,000
Regulatory Asset, Amortization Period		30 years
Subsidiaries [Member] | Deferred decoupling revenue, net [Member]
Regulatory Assets [Line Items]
Regulatory Assets		$ 51,838,000	31,398,000
Regulatory Asset, Amortization Period		2 years
Subsidiaries [Member] | Chelan PUD contract initiation
Regulatory Assets [Line Items]
Regulatory Assets		$ 48,435,000	55,523,000
Regulatory Asset, Amortization Period		6 years 9 months 18 days
Subsidiaries [Member] | Climate Commitment Act Recovery
Regulatory Assets [Line Items]
Regulatory Assets		$ 43,538,000	186,550,000
Subsidiaries [Member] | WUTC LNG
Regulatory Assets [Line Items]
Regulatory Assets		38,070,000	42,247,000
Subsidiaries [Member] | WUTC COVID-19
Regulatory Assets [Line Items]
Regulatory Assets		37,089,000	17,097,000
Subsidiaries [Member] | Lower Snake River
Regulatory Assets [Line Items]
Regulatory Assets		$ 35,429,000	43,220,000
Regulatory Asset, Amortization Period		12 years 4 months 24 days
Subsidiaries [Member] | Unamortized loss on reacquired debt
Regulatory Assets [Line Items]
Regulatory Assets		$ 29,680,000	31,626,000
Net Regulatory Assets, Remaining Amortization Period, Max		43 years
Net Regulatory Assets, Remaining Amortization Period, Min		3 years
Subsidiaries [Member] | Regulatory Filing Fee Deferral
Regulatory Assets [Line Items]
Regulatory Assets		$ 26,543,000	14,582,000
Regulatory Asset, Amortization Period		2 years
Subsidiaries [Member] | Various other regulatory assets
Regulatory Assets [Line Items]
Regulatory Assets		$ 107,325,000	$ 126,473,000

General Rate Case Filing (Detai

General Rate Case Filing (Details) - Subsidiaries [Member] $ in Millions			12 Months Ended
	Dec. 22, 2022 yr	Oct. 01, 2021 USD ($)	Dec. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Schedule of Regulatory Assets and Liabilities [Line Items]
Rate Plan, number of years | yr	2
General Rate Case [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Approved Debt Capital Structure, Net of Tax, Percentage	6.62%	6.80%
Public Utilities, Approved Equity Capital Structure, Percentage	49%	48.50%
Public Utilities, Approved Return on Equity, Percentage	9.40%	9.40%
Public Utilities, Allowance for Funds Used During Construction, Rate	7.16%	7.39%
Forecast
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Allowance for Funds Used During Construction, Rate			7.99%	7.65%
Forecast | General Rate Case [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Approved Equity Capital Structure, Percentage			50%	49%
Public Utilities, Approved Return on Equity, Percentage			9.90%	9.80%
Public Utilities, Allowance for Funds Used During Construction, Rate			7.64%	7.52%
Forecast | General Rate Case [Member] | Maximum
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Requested Return on Equity, Percentage			10.50%	9.95%
Electricity, US Regulated [Member] | General Rate Case [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Interim Rate Increase (Decrease), Amount		$ 48.3
Public Utilities, Interim Rate Increase (Decrease), Percentage		2.30%
Public Utilities, Approved Rate Increase (Decrease), Amount					$ 33.1	$ 247
Public Utilities, Approved Rate Increase (Decrease), Percentage					1.30%	10.80%
Electricity, US Regulated [Member] | Forecast | General Rate Case [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			$ 191	$ 378.2
Public Utilities, Approved Rate Increase (Decrease), Percentage			5.90%	13.30%
Public Utilities, Requested Rate Increase (Decrease), Percentage			8.50%	6.70%
Natural Gas, US Regulated [Member] | General Rate Case [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Interim Rate Increase (Decrease), Amount		$ 4.9
Public Utilities, Interim Rate Increase (Decrease), Percentage		0.60%
Public Utilities, Approved Rate Increase (Decrease), Amount					$ 19.5	$ 70.8
Public Utilities, Approved Rate Increase (Decrease), Percentage					1.70%	6.40%
Natural Gas, US Regulated [Member] | Forecast | General Rate Case [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount			$ 20	$ 110
Public Utilities, Approved Rate Increase (Decrease), Percentage			1.80%	10.60%
Public Utilities, Requested Rate Increase (Decrease), Percentage			2.10%	19%

Power Cost Only Rate Case (Deta

Power Cost Only Rate Case (Details) $ in Thousands	Jan. 11, 2023 USD ($)
Subsidiaries [Member] | Electricity, US Regulated [Member] | Power Cost Only Rate Case
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 0

Decoupling Filings (Details)

Decoupling Filings (Details) - Subsidiaries [Member] - Decoupling Mechanism [Member] - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Electricity, US Regulated [Member]
Regulatory Assets [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 0.2	$ 0
Electricity, US Regulated [Member] | Maximum
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage	3%
Natural Gas, US Regulated [Member] | Maximum
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage	5%
Natural Gas [Member]
Regulatory Assets [Line Items]
Contract with Customer, Liability, Revenue Recognized	$ 0	$ 0

Schedule of Power Cost Adjustme

Schedule of Power Cost Adjustment Mechanism (Details) - Subsidiaries [Member] $ in Millions		12 Months Ended
	Apr. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount	$ 98.2
Annual Power Cost Variability, Interest		$ 3.9	$ 3.9
Under-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount			51.1	$ 110.1
Under-collection | Customer's share
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount			24.9	71.1
Under-collection | Customer's share | Range 1
Regulatory Assets [Line Items]
Annual Power Cost Variability		0
Under-collection | Customer's share | Range 2
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.50
Under-collection | Customer's share | Range 3
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.90
Under-collection | Companys share
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount			$ 26.2	$ 39
Under-collection | Companys share | Range 1
Regulatory Assets [Line Items]
Annual Power Cost Variability		1
Under-collection | Companys share | Range 2
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.50
Under-collection | Companys share | Range 3
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.10
Over-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		$ 123.3
Over-collection | Customer's share
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		$ 86.5
Over-collection | Customer's share | Range 1
Regulatory Assets [Line Items]
Annual Power Cost Variability		0
Over-collection | Customer's share | Range 2
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.65
Over-collection | Customer's share | Range 3
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.90
Over-collection | Companys share | Range 1
Regulatory Assets [Line Items]
Annual Power Cost Variability		1
Over-collection | Companys share | Range 2
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.35
Over-collection | Companys share | Range 3
Regulatory Assets [Line Items]
Annual Power Cost Variability		0.10

Power Cost Adjustment Clause Fi

Power Cost Adjustment Clause Filing (Details) - Subsidiaries [Member] - USD ($) $ in Millions		12 Months Ended		13 Months Ended
	Apr. 30, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2024
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount	$ 98.2
Under-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		$ 51.1	$ 110.1
Customer's share | Under-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		24.9	71.1
Companys share | Under-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		26.2	39
Customer's share plus interest [Member] | Under-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		22.2	76.4
Customer's share plus interest [Member] | Maximum Power
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		20	$ 20
PCA Mechanism [Member]
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage				0.90%
PCA Mechanism [Member] | Customer's share | Under-collection
Regulatory Assets [Line Items]
Annual Power Cost Variability, Amount		$ 24.9

Purchased Gas Adjustment Mechan

Purchased Gas Adjustment Mechanism (Details) - Subsidiaries [Member] - USD ($) $ in Thousands				1 Months Ended	12 Months Ended
	Nov. 01, 2024	Nov. 01, 2023	Nov. 01, 2022	Nov. 30, 2022	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Regulatory Assets [Line Items]
PGA Receivable					$ (58,657)	$ (132,082)	$ (3,536)
Purchased Gas Adjustment [Member]
Regulatory Assets [Line Items]
Purchased natural gas costs					416,067	404,897
Purchased natural gas costs, recoverable					(336,170)	(521,882)
Purchased natural gas adjustment, interest					(6,472)	(7,639)
Purchased natural gas costs, credit for CP settlement	$ 28,100	$ 28,100		$ 24,200	$ 0	$ (3,922)
Public Utilities, Approved Rate Increase (Decrease), Amount	124,400	(309,400)	$ 155,300
Purchased natural gas costs, commodity deferrals	142,800
Schedule 101
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		(93,900)	142,100
Schedule 106
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	127,000	$ (215,500)	$ 13,200
Purchased Gas Adjustment, Schedule 101
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 2,600

Narrative (Details)

Narrative (Details) - USD ($)		12 Months Ended
	Jan. 01, 2025	Dec. 31, 2026	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Jan. 01, 2026	Jan. 01, 2018
Regulatory Assets [Line Items]
Depreciation and amortization				$ 787,986,000	$ 751,335,000	$ 663,232,000
Accrual for Environmental Loss Contingencies				73,000,000
Subsidiaries [Member]
Regulatory Assets [Line Items]
Depreciation and amortization				781,325,000	744,629,000	657,349,000
Storm Damage Costs Incurred During Period				74,500,000	8,100,000
Public Utilities, Rate Case, Deferred Storm Costs Threshold				10,000,000				$ 10,000,000
Public Utilities, Rate Case, Deferred Storm Qualifying Costs				500,000
Subsidiaries [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Rate Case, Deferred Storm Costs Threshold	$ 9,400,000						$ 9,600,000
Subsidiaries [Member] | Storm that occurred in 2022
Regulatory Assets [Line Items]
Storm Damage Costs Deferred During Period						$ 2,100,000
Subsidiaries [Member] | Storm that occurred in 2023
Regulatory Assets [Line Items]
Storm Damage Costs Deferred During Period					0
Subsidiaries [Member] | Storm that occurred in 2024
Regulatory Assets [Line Items]
Storm Damage Costs Deferred During Period				58,900,000
Subsidiaries [Member] | General Rate Case [Member] | Natural Gas, US Regulated [Member]
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 19,500,000	$ 70,800,000
Public Utilities, Approved Rate Increase (Decrease), Percentage				1.70%	6.40%
Subsidiaries [Member] | General Rate Case [Member] | Natural Gas, US Regulated [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 20,000,000	$ 110,000,000
Public Utilities, Approved Rate Increase (Decrease), Percentage		1.80%	10.60%
Subsidiaries [Member] | General Rate Case [Member] | Electricity, US Regulated [Member]
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ 33,100,000	$ 247,000,000
Public Utilities, Approved Rate Increase (Decrease), Percentage				1.30%	10.80%
Subsidiaries [Member] | General Rate Case [Member] | Electricity, US Regulated [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount		$ 191,000,000	$ 378,200,000
Public Utilities, Approved Rate Increase (Decrease), Percentage		5.90%	13.30%
Subsidiaries [Member] | Colstrip Adjustment Rider | Natural Gas, US Regulated [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Percentage	0.10%
Subsidiaries [Member] | Colstrip Adjustment Rider | Electricity, US Regulated [Member] | Forecast
Regulatory Assets [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 4,100,000

Environmental Remediation (Deta

Environmental Remediation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	$ 1,421,272	$ 1,218,244
Accrual for Environmental Loss Contingencies, Payments	(10)	(495)
Accrual for Environmental Loss Contingencies, Revision in Estimates	725	45,883
Liabilities Subject to Compromise, Environmental Contingencies	$ 181,155	180,440	$ 135,052
Environmental Loss Contingency Statement Of Financial Position Extensible Enumeration Not Disclosed Flag	73.0 million
Environmental Remediation
Schedule of Regulatory Assets and Liabilities [Line Items]
Regulatory Assets	$ 180,245	182,697	$ 141,893
Regulatory Asset, Amortization, Net of Recoveries	(3,732)	(4,521)
Regulatory Asset, Revision In Estimates	$ 1,280	$ 45,325

Regulation and Rates - CCA (Det

Regulation and Rates - CCA (Details) - Subsidiaries [Member] - USD ($) $ in Thousands	Jan. 01, 2024	Dec. 31, 2024
Schedule of Regulatory Assets and Liabilities [Line Items]
Deferred Emission Compliance Costs, Regulatory Liability		$ 97,700
Natural Gas, US Regulated [Member]
Schedule of Regulatory Assets and Liabilities [Line Items]
Deferred Emission Compliance Auction Proceeds, Regulatory Asset		$ 43,500
Natural Gas, US Regulated [Member] | Climate Commitment Act
Schedule of Regulatory Assets and Liabilities [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 29,100

Dividend Payment Restrictions (

Dividend Payment Restrictions (Details) $ in Billions	12 Months Ended
	Dec. 31, 2024 USD ($)
Parent [Line Items]
Retained Earnings, Unappropriated	$ 1.8
Dividends, Earnings Before Interest, Tax, Deprecation and Amortization Ratio, Threshold For Dividend Payment	2
EBITDA Interest Expense Ratio	3.5
EBITDA to Interest Expense Denominator	1
Dividends, Earnings Before Interest, Tax, Deprecation and Amortization Ratio at Period End	1
Subsidiaries [Member]
Parent [Line Items]
Dividends, Common Equity Ratio, Threshold For Dividend Payment	44%
Dividends, Earnings Before Interest, Tax, Deprecation and Amortization Ratio, Threshold For Dividend Payment	3
Dividends, Common Equity Ratio at Period End	48.10%
EBITDA Interest Expense Ratio	4.6
EBITDA to Interest Expense Denominator	1
Dividends, Earnings Before Interest, Tax, Deprecation and Amortization Ratio at Period End	1

Utility Plant (Details)

Utility Plant (Details) $ in Thousands			12 Months Ended
	Jan. 26, 2024 USD ($)	Dec. 01, 2023 USD ($)	Dec. 31, 2024 USD ($) unit MW	Dec. 31, 2023 USD ($)
Public Utility, Property, Plant and Equipment
Accumulated amortization of capital leases			$ 18,300	$ 13,200
Utility Plant
Distribution plant			8,983,586	8,298,893
Production plant			3,310,663	3,173,514
Transmission plant			1,908,891	1,595,566
General plant			805,960	717,017
Intangible plant (including capitalized software)2			716,038	586,749
Plant acquisition adjustment			242,827	242,826
Underground storage			50,047	46,761
Liquefied natural gas storage			256,144	224,337
Plant held for future use			59,657	59,409
Recoverable cushion gas			8,784	8,784
Plant not classified			733,184	1,032,004
Finance leases, net of accumulated amortization3			91,045	95,114
Less: Accumulated depreciation and amortization			(5,101,926)	(4,643,833)
Subtotal			12,064,900	11,437,141
Construction work in progress			1,577,695	1,156,265
Net utility plant			$ 13,642,595	12,593,406
Minimum
Public Utility, Property, Plant and Equipment
Distribution plant, Estimated Useful Life			7 years
Production plant, Estimated Useful Life			12 years
Transmission plant, Estimated Useful Life			44 years
General plant, Estimated Useful Life			5 years
Public Utilities, Property, Plant and Equipment, Intangible, Estimated Useful Life 1			3 years
Underground storage, Estimated Useful Life			25 years
Liquefied natural gas storage, Estimated Useful Life			25 years
Minimum | Franchise Rights [Member]
Public Utility, Property, Plant and Equipment
General plant, Estimated Useful Life			10 years
Minimum | Software and Software Development Costs [Member]
Public Utility, Property, Plant and Equipment
General plant, Estimated Useful Life			3 years
Maximum
Public Utility, Property, Plant and Equipment
Distribution plant, Estimated Useful Life			65 years
Production plant, Estimated Useful Life			90 years
Transmission plant, Estimated Useful Life			75 years
General plant, Estimated Useful Life			75 years
Public Utilities, Property, Plant and Equipment, Intangible, Estimated Useful Life 1			50 years
Underground storage, Estimated Useful Life			60 years
Liquefied natural gas storage, Estimated Useful Life			50 years
Maximum | Franchise Rights [Member]
Public Utility, Property, Plant and Equipment
General plant, Estimated Useful Life			50 years
Maximum | Software and Software Development Costs [Member]
Public Utility, Property, Plant and Equipment
General plant, Estimated Useful Life			10 years
Subsidiaries [Member]
Utility Plant
Distribution plant			$ 10,474,294	9,804,018
Production plant			3,928,187	3,805,294
Transmission plant			2,015,060	1,701,878
General plant			826,918	738,996
Intangible plant (including capitalized software)2			706,576	577,291
Plant acquisition adjustment			282,792	282,792
Underground storage			63,004	60,171
Liquefied natural gas storage			257,909	226,208
Plant held for future use			59,809	59,561
Recoverable cushion gas			8,784	8,784
Plant not classified			733,184	1,032,002
Finance leases, net of accumulated amortization3			91,045	95,114
Less: Accumulated depreciation and amortization			(7,382,662)	(6,954,968)
Subtotal			12,064,900	11,437,141
Construction work in progress			1,577,695	1,156,265
Net utility plant			13,642,595	$ 12,593,406
Subsidiaries [Member] | Beaver Creek Wind Project
Utility Plant
Asset Acquisition, Price of Acquisition, Expected	$ 145,400
Subsidiaries [Member] | GE Renewables North America, LLC | Beaver Creek Wind Project
Utility Plant
Asset Acquisition, Price of Acquisition, Expected		$ 266,900
Subsidiaries [Member] | Beaver Creek Wind Project
Utility Plant
Construction work in progress			$ 506,500
Nameplate Capacity | MW			248
Number of Windmills | unit			88
Subsidiaries [Member] | Beaver Creek Wind Project | Caithness Beaver Creek, LLC
Utility Plant
Asset Acquisition, Consideration Transferred		$ 44,600	$ 23,800
Subsidiaries [Member] | Beaver Creek Wind Project | GE Renewables North America, LLC
Utility Plant
Asset Acquisition, Consideration Transferred			$ 234,600

Utility Plant - Jointly Owned U

Utility Plant - Jointly Owned Utility Plant (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Colstrip Units 3 & 4
Jointly Owned Utility Plant Interests
Plant in Service at Cost	$ 324,451
Construction Work in Progress	0
Accumulated Depreciation	(233,934)
Frederickson 1
Jointly Owned Utility Plant Interests
Plant in Service at Cost	68,006
Construction Work in Progress	0
Accumulated Depreciation	(32,767)
Jackson Prairie [Member]
Jointly Owned Utility Plant Interests
Plant in Service at Cost	48,174
Construction Work in Progress	688
Accumulated Depreciation	(14,196)
Tacoma LNG [Member]
Jointly Owned Utility Plant Interests
Plant in Service at Cost	497,290
Construction Work in Progress	3,545
Accumulated Depreciation	$ (36,847)
Subsidiaries [Member] | Colstrip Units 3 & 4
Jointly Owned Utility Plant Interests
Company’s Ownership Share	25%
Plant in Service at Cost	$ 581,467
Construction Work in Progress	0
Accumulated Depreciation	$ (490,950)
Subsidiaries [Member] | Frederickson 1
Jointly Owned Utility Plant Interests
Company’s Ownership Share	49.85%
Plant in Service at Cost	$ 73,658
Construction Work in Progress	0
Accumulated Depreciation	$ (38,418)
Subsidiaries [Member] | Jackson Prairie [Member]
Jointly Owned Utility Plant Interests
Company’s Ownership Share	33.34%
Plant in Service at Cost	$ 63,004
Construction Work in Progress	688
Accumulated Depreciation	(29,025)
Subsidiaries [Member] | Tacoma LNG [Member]
Jointly Owned Utility Plant Interests
Plant in Service at Cost	246,893
Construction Work in Progress	240
Accumulated Depreciation	$ (17,916)

Utility Plant - Schedule of Ass

Utility Plant - Schedule of Asset Retirement Obligation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Tacoma LNG [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Decommissioning Liability, Noncurrent	$ 4,200	$ 4,100
Subsidiaries [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
ARO beginning balance	207,034	209,406
Relief of liability	(6,049)	(5,998)
Revisions in estimated cash flows	9,471	(2,206)
Accretion expense	6,676	5,832
Asset Retirement Obligation, Ending Balance	235,943	207,034
New ARO recognized in the period	18,811	0
Decommissioning Liability, Noncurrent	6,000	6,000
Puget LNG [Member] | Tacoma LNG [Member]
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Decommissioning Liability, Noncurrent	$ 4,100	$ 4,000

Utility Plant - Narrative (Deta

Utility Plant - Narrative (Details) $ in Thousands				12 Months Ended
	Aug. 30, 2024 USD ($)	Dec. 22, 2023 USD ($)	Dec. 01, 2023 USD ($)	Dec. 31, 2024 USD ($) unit MW	Dec. 31, 2023 USD ($)
Jointly Owned Utility Plant Interests
Construction work in progress				$ 1,577,695	$ 1,156,265
Tacoma LNG [Member]
Jointly Owned Utility Plant Interests
Decommissioning Liability, Noncurrent				4,200	4,100
Subsidiaries [Member]
Jointly Owned Utility Plant Interests
Decommissioning Liability, Noncurrent				6,000	6,000
Construction work in progress				$ 1,577,695	1,156,265
Subsidiaries [Member] | Appaloosa Solar Project
Jointly Owned Utility Plant Interests
Asset Acquisition, Price of Acquisition, Expected	$ 266,800
Subsidiaries [Member] | Beaver Creek Wind Project
Jointly Owned Utility Plant Interests
Nameplate Capacity | MW				248
Construction work in progress				$ 506,500
Number of Windmills | unit				88
Subsidiaries [Member] | Beaver Creek Wind Project | Caithness Beaver Creek, LLC
Jointly Owned Utility Plant Interests
Asset Acquisition, Consideration Transferred			$ 44,600	$ 23,800
Subsidiaries [Member] | Beaver Creek Wind Project | GE Renewables North America, LLC
Jointly Owned Utility Plant Interests
Asset Acquisition, Consideration Transferred				$ 234,600
Subsidiaries [Member] | Appaloosa Solar Project
Jointly Owned Utility Plant Interests
Nameplate Capacity | MW				142
Construction work in progress				$ 27,200
Subsidiaries [Member] | Appaloosa Solar Project | HQC Solar Holdings 1, LLC
Jointly Owned Utility Plant Interests
Asset Acquisition, Consideration Transferred		$ 20,300		18,600
Subsidiaries [Member] | Colstrip Units 1 and 2 [Member]
Jointly Owned Utility Plant Interests
Decommissioning Liability, Noncurrent				7,900	0
Subsidiaries [Member] | Beaver Creek Wind Project
Jointly Owned Utility Plant Interests
Decommissioning Liability, Noncurrent				18,800	0
Puget LNG [Member] | Tacoma LNG [Member]
Jointly Owned Utility Plant Interests
Decommissioning Liability, Noncurrent				$ 4,100	$ 4,000

Long-Term Debt (Schedule of Lon

Long-Term Debt (Schedule of Long-Term Debt Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	May 31, 2022	May 16, 2022
Debt Instrument [Line Items]
Total PSE long-term debt	$ 8,023,860
Long Term Debt, Reconciliation, Fair Value Adjustment	(131,326)	$ (139,834)
Unamortized discount on senior notes	(5,780)	(7,571)
Long-term Debt, Excluding Current Maturities	7,423,919	7,036,642
Short-term debt	$ 378,400	598,100
Working Capital Needs
Debt Instrument [Line Items]
Current borrowing capacity of line of credit				$ 800,000
Senior Secured Note | 3.650% Senior Secured Note Due 2025 [Member]
Debt Instrument [Line Items]
Stated interest rate percent	3.65%
Total PSE long-term debt	$ 0	400,000
Senior Secured Note | 4.100% Senior Secured Note Due 2030
Debt Instrument [Line Items]
Stated interest rate percent	4.10%
Total PSE long-term debt	$ 650,000	650,000
Senior Secured Note | 2.379% Senior Secured Note Due 2028
Debt Instrument [Line Items]
Stated interest rate percent	2.379%
Total PSE long-term debt	$ 500,000	500,000
Senior Secured Note | 4.224% Senior Secured Note Due 2032
Debt Instrument [Line Items]
Stated interest rate percent	4.224%
Total PSE long-term debt	$ 450,000	450,000
Subsidiaries [Member]
Debt Instrument [Line Items]
Total PSE long-term debt	6,023,860
Unamortized discount on senior notes	(45,835)	(39,813)
Long-term Debt, Excluding Current Maturities	5,961,025	5,184,047
Short-term debt	$ 40,000	336,600
Subsidiaries [Member] | Working Capital Needs
Debt Instrument [Line Items]
Current borrowing capacity of line of credit			$ 800,000
Subsidiaries [Member] | Senior Notes and First Mortgage Bonds | 7.150% Series Due 2025
Debt Instrument [Line Items]
Stated interest rate percent	7.15%
Total PSE long-term debt	$ 0	15,000
Subsidiaries [Member] | Senior Notes and First Mortgage Bonds | 7.200% Series Due 2025
Debt Instrument [Line Items]
Stated interest rate percent	7.20%
Total PSE long-term debt	$ 0	2,000
Subsidiaries [Member] | Pollution Control Bonds | 3.900% Series Due 2031
Debt Instrument [Line Items]
Stated interest rate percent	3.90%
Total PSE long-term debt	$ 138,460	138,460
Subsidiaries [Member] | Pollution Control Bonds | 4.000% Series Due 2031
Debt Instrument [Line Items]
Stated interest rate percent	4%
Total PSE long-term debt	$ 23,400	23,400
Subsidiaries [Member] | Senior Secured Note | 7.020% Series Due 2027
Debt Instrument [Line Items]
Stated interest rate percent	7.02%
Total PSE long-term debt	$ 300,000	300,000
Subsidiaries [Member] | Senior Secured Note | 7.000% Series Due 2029
Debt Instrument [Line Items]
Stated interest rate percent	7%
Total PSE long-term debt	$ 100,000	100,000
Subsidiaries [Member] | Senior Secured Note | 5.483% Series Due 2035
Debt Instrument [Line Items]
Stated interest rate percent	5.483%
Total PSE long-term debt	$ 250,000	250,000
Subsidiaries [Member] | Senior Secured Note | 6.724% Series Due 2036
Debt Instrument [Line Items]
Stated interest rate percent	6.724%
Total PSE long-term debt	$ 250,000	250,000
Subsidiaries [Member] | Senior Secured Note | 6.274% Series Due 2037
Debt Instrument [Line Items]
Stated interest rate percent	6.274%
Total PSE long-term debt	$ 300,000	300,000
Subsidiaries [Member] | Senior Secured Note | 5.757% Series Due 2039
Debt Instrument [Line Items]
Stated interest rate percent	5.757%
Total PSE long-term debt	$ 350,000	350,000
Subsidiaries [Member] | Senior Secured Note | 5.795% Series Due 2040
Debt Instrument [Line Items]
Stated interest rate percent	5.795%
Total PSE long-term debt	$ 325,000	325,000
Subsidiaries [Member] | Senior Secured Note | 5.764% Series Due 2040
Debt Instrument [Line Items]
Stated interest rate percent	5.764%
Total PSE long-term debt	$ 250,000	250,000
Subsidiaries [Member] | Senior Secured Note | 4.434% Series Due 2041
Debt Instrument [Line Items]
Stated interest rate percent	4.434%
Total PSE long-term debt	$ 250,000	250,000
Subsidiaries [Member] | Senior Secured Note | 5.638% Series Due 2041
Debt Instrument [Line Items]
Stated interest rate percent	5.638%
Total PSE long-term debt	$ 300,000	300,000
Subsidiaries [Member] | Senior Secured Note | 4.300% Series Due 2045
Debt Instrument [Line Items]
Stated interest rate percent	4.30%
Total PSE long-term debt	$ 425,000	425,000
Subsidiaries [Member] | Senior Secured Note | 4.223% Series Due 2048
Debt Instrument [Line Items]
Stated interest rate percent	4.223%
Total PSE long-term debt	$ 600,000	600,000
Subsidiaries [Member] | Senior Secured Note | 3.250% Senior Secured Note Due 2049 [Member]
Debt Instrument [Line Items]
Stated interest rate percent	3.25%
Total PSE long-term debt	$ 450,000	450,000
Subsidiaries [Member] | Senior Secured Note | 4.700% Series Due 2051
Debt Instrument [Line Items]
Stated interest rate percent	4.70%
Total PSE long-term debt	$ 45,000	45,000
Subsidiaries [Member] | Senior Secured Note | 2.893% Senior Secured Note Due 2051
Debt Instrument [Line Items]
Stated interest rate percent	2.893%
Total PSE long-term debt	$ 450,000	450,000
Subsidiaries [Member] | Senior Secured Note | 5.448% Series Due 2053
Debt Instrument [Line Items]
Stated interest rate percent	5.448%
Total PSE long-term debt	$ 400,000	400,000
Subsidiaries [Member] | Senior Secured Note | 5.330% Series Due 2034
Debt Instrument [Line Items]
Stated interest rate percent	5.33%
Total PSE long-term debt	$ 400,000	0
Subsidiaries [Member] | Senior Secured Note | 5.685% Series Due 2054
Debt Instrument [Line Items]
Stated interest rate percent	5.685%
Total PSE long-term debt	$ 400,000	$ 0

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended
	Aug. 31, 2022	Mar. 31, 2022	Dec. 31, 2024	Jun. 11, 2024	Dec. 31, 2023	May 18, 2023
Debt Instrument [Line Items]
Total PSE long-term debt			$ 8,023,860
Long-term debt			8,023,860
Line of Credit Facility, Maximum Borrowing Capacity			1,300,000
Debt discount, issuance costs and other			182,941		$ 187,218
Line of Credit, Current			338,400		261,500
Debt Instrument, Unused Borrowing Capacity, Amount			550,000
Debt Instrument, Maximum Borrowing Capacity		$ 1,000,000
Senior Secured Note | 2.379% Senior Secured Note Due 2028
Debt Instrument [Line Items]
Total PSE long-term debt			500,000		500,000
Long-term debt			$ 500,000		500,000
Stated interest rate percent			2.379%
Senior Secured Note | 4.224% Senior Secured Note Due 2032
Debt Instrument [Line Items]
Total PSE long-term debt			$ 450,000		450,000
Long-term debt			$ 450,000		450,000
Stated interest rate percent			4.224%
Senior Notes | 5.448% Senior Secured Note Due 2053
Debt Instrument [Line Items]
Debt Instrument, Face Amount						$ 400,000
Subsidiaries [Member]
Debt Instrument [Line Items]
Total PSE long-term debt			$ 6,023,860
Long-term debt			6,023,860
Line of Credit Facility, Maximum Borrowing Capacity			1,400,000
Debt discount, issuance costs and other			45,835		39,813
Debt Instrument, Unused Borrowing Capacity, Amount			200,000
Debt Instrument, Maximum Borrowing Capacity	$ 1,400,000
Subsidiaries [Member] | Senior Secured Note | 4.223% Series Due 2048
Debt Instrument [Line Items]
Total PSE long-term debt			600,000		600,000
Long-term debt			$ 600,000		600,000
Stated interest rate percent			4.223%
Subsidiaries [Member] | Senior Secured Note | 2.893% Senior Secured Note Due 2051
Debt Instrument [Line Items]
Total PSE long-term debt			$ 450,000		450,000
Long-term debt			$ 450,000		$ 450,000
Stated interest rate percent			2.893%
Subsidiaries [Member] | Senior Notes | 5.448% Senior Secured Note Due 2053
Debt Instrument [Line Items]
Stated interest rate percent						5.448%
Subsidiaries [Member] | Senior Notes | 5.330% Senior Secured Note Due 2034
Debt Instrument [Line Items]
Stated interest rate percent				5.33%
Debt Instrument, Face Amount				$ 400,000
Subsidiaries [Member] | Senior Notes | 5.685% Senior Secured Note Due 2054
Debt Instrument [Line Items]
Stated interest rate percent				5.685%
Debt Instrument, Face Amount				$ 400,000

Long-Term Debt (Schedule of Mat

Long-Term Debt (Schedule of Maturities of Long-Term Debt) (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Maturities of Long-term Debt [Abstract]
2025	$ 417,000
2026	0
2027	300,000
2028	500,000
2029	100,000
Thereafter	6,706,860
Total	8,023,860
Subsidiaries [Member]
Maturities of Long-term Debt [Abstract]
2025	17,000
2026	0
2027	300,000
2028	0
2029	100,000
Thereafter	5,606,860
Total	6,023,860
Parent Company [Member]
Maturities of Long-term Debt [Abstract]
2025	400,000
2026	0
2027	0
2028	500,000
2029	0
Thereafter	1,100,000
Total	$ 2,000,000

Liquidity Facilities and Othe_2

Liquidity Facilities and Other Financing Arrangements (Details) - USD ($) $ in Thousands			12 Months Ended
	Jun. 17, 2024	Aug. 31, 2023	Dec. 31, 2024	Dec. 31, 2023	May 31, 2022	May 16, 2022
Short-term Debt [Line Items]
Short-term debt			$ 378,400	$ 598,100
Line of Credit Facility, Maximum Borrowing Capacity			1,300,000
Proceeds from Lines of Credit		$ 100,000
Line of Credit, Current			338,400	261,500
Working Capital Needs
Short-term Debt [Line Items]
Current borrowing capacity of line of credit						$ 800,000
Subsidiaries [Member]
Short-term Debt [Line Items]
Short-term debt			$ 40,000	$ 336,600
Weighted-average interest rate on short-term debt (percent)			8.50%	9%
Line of Credit Facility, Current Same-Day Borrowing Capacity			$ 75,000
Line of Credit Facility, Maximum Borrowing Capacity			$ 1,400,000
Maximum capitalization percentage			65%
Derivative, Basis Spread on Variable Rate			1.25%
Line of Credit, Unused Capacity, Commitment Fee Percentage			0.175%
Promissory Note Outstanding, Amount			$ 0
Proceeds from Contributed Capital	$ 292,800
Subsidiaries [Member] | Standby Letters of Credit
Short-term Debt [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity			150,000
Subsidiaries [Member] | Working Capital Needs
Short-term Debt [Line Items]
Current borrowing capacity of line of credit					$ 800,000
Subsidiaries [Member] | Purchase Power Contract
Short-term Debt [Line Items]
Posted Collateral			15,000
Subsidiaries [Member] | Purchase Power Contract | Standby Letters of Credit | Purchase Power Contract 1
Short-term Debt [Line Items]
Current borrowing capacity of line of credit			60,000
Subsidiaries [Member] | Purchase Power Contract | Standby Letters of Credit | Purchase Power Contract 2
Short-term Debt [Line Items]
Current borrowing capacity of line of credit			13,500
Subsidiaries [Member] | Letter of Credit | Working Capital Needs
Short-term Debt [Line Items]
Current borrowing capacity of line of credit			1,900
Subsidiaries [Member] | Letter of Credit | Energy Dedging Activities
Short-term Debt [Line Items]
Current borrowing capacity of line of credit			6,600
Subsidiaries [Member] | Line of Credit [Member] | Promissory Note with Puget Energy
Short-term Debt [Line Items]
Current borrowing capacity of line of credit			200,000
Parent
Short-term Debt [Line Items]
Short-term debt			$ 338,400	$ 261,500
Revolving Credit Facility [Member]
Short-term Debt [Line Items]
Basis spread on variable rate (percent)			1.75%
Line of Credit Facility, Commitment Fee Percentage			0.275%
Debt Instrument, Secured Overnight Financing Rate Adjustment			0.10%
Revolving Credit Facility [Member] | Subsidiaries [Member]
Short-term Debt [Line Items]
Line of Credit Facility, Fair Value of Amount Outstanding			$ 0
Debt Instrument, Secured Overnight Financing Rate Adjustment			0.10%

Leases (Details)

Leases (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Sep. 01, 2027 USD ($)	Aug. 01, 2027 USD ($)	Oct. 01, 2025 USD ($)	Jan. 01, 2025 USD ($)	Nov. 07, 2024 MW	Sep. 20, 2023 MW
Lessee, Lease, Description [Line Items]
Lease, Remaining Lease Term	45 years
Subsidiaries [Member]
Lessee, Lease, Description [Line Items]
Right-of-Use, Modification, Operating	$ 1,996	$ 6,912
Lessee, Finance Lease, Lease Not yet Commenced, Capacity | MW							650,000,000	132,500,000
Subsidiaries [Member] | Forecast
Lessee, Lease, Description [Line Items]
Lessee, Finance Lease, Lease Not yet Commenced, Term of Contract					5 years
Lessee, Finance Lease, Lease Not Yet Commenced, Fixed Consideration					$ 91,000
Subsidiaries [Member] | Puyallup Service Center | Forecast
Lessee, Lease, Description [Line Items]
Lessee, Finance Lease, Lease Not yet Commenced, Term of Contract					20 years
Lessee, Finance Lease, Lease Not Yet Commenced, Fixed Consideration					$ 116,000
Subsidiaries [Member] | Greenwater Battery Storage | Forecast
Lessee, Lease, Description [Line Items]
Lessee, Finance Lease, Lease Not yet Commenced, Term of Contract				20 years
Lessee, Finance Lease, Lease Not Yet Commenced, Fixed Consideration				$ 744,000
Subsidiaries [Member] | Mt Vernon Battery Storage | Forecast
Lessee, Lease, Description [Line Items]
Lessee, Finance Lease, Lease Not yet Commenced, Term of Contract			25 years
Lessee, Finance Lease, Lease Not Yet Commenced, Fixed Consideration			$ 856,200
Subsidiaries [Member] | Grays Harbor Tolling | Forecast
Lessee, Lease, Description [Line Items]
Lessee, Finance Lease, Lease Not Yet Commenced, Fixed Consideration						$ 486,000

Leases (Schedule of Operating L

Leases (Schedule of Operating Lease Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Operating Leased Assets [Line Items]
Finance Lease, Right-of-Use Asset, Amortization	$ 3,915	$ 3,891
Finance Lease, Interest Expense	3,192	3,237
Finance Lease, Cost	7,107	7,128
Operating Lease, Cost	$ 24,993	$ 23,891
Finance Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]	Other	Other
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Public Utilities, Property, Plant and Equipment, Net	Public Utilities, Property, Plant and Equipment, Net
Subsidiaries [Member] | Land [Member]
Operating Leased Assets [Line Items]
Operating Lease, Cost	$ 1,700	$ 1,700

Leases (Cash paid) (Details)

Leases (Cash paid) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Lessee, Lease, Description [Line Items]
Operating Lease, Payments	$ 17,038	$ 15,990
Operating Lease, Payments, Use	7,955	7,901
Finance Lease, Interest Payment on Liability	3,192	3,237
Finance Lease, Principal Payments	3,915	3,891
Operating Lease, Cost	24,993	23,891
Subsidiaries [Member]
Lessee, Lease, Description [Line Items]
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	4,093	10,462
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	1,832	1,245
Right-of-Use, Modification, Operating	1,996	6,912
Subsidiaries [Member] | Land [Member]
Lessee, Lease, Description [Line Items]
Operating Lease, Cost	$ 1,700	$ 1,700

Leases (Balance Sheet) (Details

Leases (Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Operating lease right-of-use asset	$ 181,397	$ 194,321
Operating lease liabilities	22,761	21,629
Operating lease liabilities	166,700	180,754
Operating Lease, Liability	189,461	202,383
Finance Lease, Right-of-Use Asset	91,045	95,114
Finance Lease, Liability, Current	3,786	3,371
Finance lease liabilities	96,850	99,512
Finance Lease, Liability	$ 100,636	$ 102,883
Operating Lease, Weighted Average Remaining Lease Term	21 years 2 months 12 days	21 years 3 months 18 days
Finance Lease, Weighted Average Remaining Lease Term	16 years 10 months 24 days	18 years
Operating Lease, Weighted Average Discount Rate, Percent	3.76%	3.75%
Finance Lease, Weighted Average Discount Rate, Percent	3.10%	3.08%
Operating Leased Assets [Line Items]
Finance Lease, Right-of-Use Asset	$ 91,045	$ 95,114
Common Plant
Leases [Abstract]
Finance Lease, Right-of-Use Asset	53,594	55,756
Operating Leased Assets [Line Items]
Finance Lease, Right-of-Use Asset	53,594	55,756
Natural Gas Processing Plant
Leases [Abstract]
Finance Lease, Right-of-Use Asset	310	0
Operating Leased Assets [Line Items]
Finance Lease, Right-of-Use Asset	310	0
Electric Transmission
Leases [Abstract]
Finance Lease, Right-of-Use Asset	37,141	39,358
Operating Leased Assets [Line Items]
Finance Lease, Right-of-Use Asset	$ 37,141	$ 39,358

Leases (Remaining Cash Payments

Leases (Remaining Cash Payments) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Leases [Abstract]
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months	$ 24,687
Lessee, Operating Lease, Liability, Payments, Due Year Two	24,858
Lessee, Operating Lease, Liability, Payments, Due Year Three	24,469
Lessee, Operating Lease, Liability, Payments, Due Year Four	21,680
Lessee, Operating Lease, Liability, Payments, Due Year Five	12,622
Lessee, Operating Lease, Liability, Payments, Due after Year Five	153,937
Lessee, Operating Lease, Liability, Payments, Due	262,253
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(72,792)
Operating Lease, Liability	189,461	$ 202,383
Finance Lease, Liability, Payments, Due Next Twelve Months	7,097
Finance Lease, Liability, Payments, Due Year Two	7,140
Finance Lease, Liability, Payments, Due Year Three	7,023
Finance Lease, Liability, Payments, Due Year Four	7,106
Finance Lease, Liability, Payments, Due Year Five	6,964
Finance Lease, Liability, Payments, Due after Year Five	96,138
Finance Lease, Liability, Payment, Due	131,468
Finance Lease, Liability, Undiscounted Excess Amount	(30,832)
Finance Lease, Liability	$ 100,636	$ 102,883

Accounting for Derivative Ins_3

Accounting for Derivative Instruments and Hedging Activities (Schedule of Derivative Assets and Liabilities) (Details) $ in Thousands, MMBTU in Millions	Dec. 31, 2024 USD ($) MMBTU	Dec. 31, 2023 USD ($) MMBTU
Derivative [Line Items]
Assets, Current	$ 32,591	$ 74,225
Assets, Long-term	6,245	35,324
Total derivative assets	38,800
Liabilities, Current	218,443	185,788
Liabilities, Long-term	171,488	38,049
Total derivative liabilities	389,900
Not Designated as Hedging Instrument
Derivative [Line Items]
Assets, Current	32,591	74,225
Assets, Long-term	6,245	35,324
Total derivative assets	38,836	109,549
Liabilities, Current	218,443	185,788
Liabilities, Long-term	171,488	38,049
Total derivative liabilities	$ 389,931	$ 223,837
Not Designated as Hedging Instrument | Electric Generation Fuel
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	283.5	315.6
Not Designated as Hedging Instrument | Purchased Electricity
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	13.3	2.3
Not Designated as Hedging Instrument | Natural Gas Portfolio
Derivative [Line Items]
Total derivative assets	$ 3,495	$ 16,521
Total derivative liabilities	70,425	96,898
Not Designated as Hedging Instrument | Electric Portfolio
Derivative [Line Items]
Total derivative assets	35,341	93,028
Total derivative liabilities	$ 319,506	$ 126,939
Not Designated as Hedging Instrument | Gas Derivatives
Derivative [Line Items]
Derivative, Nonmonetary Notional Amount | MMBTU	269	301

Accounting for Derivative Ins_4

Accounting for Derivative Instruments and Hedging Activities (Offsetting) (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Derivative Asset, Fair Value, Amount Offset Against Collateral [Abstract]
Total derivative assets	$ 38,800
Derivative Liability, Fair Value, Amount Offset Against Collateral [Abstract]
Total derivative liabilities	389,900
Commodity Contract [Member]
Derivative Asset, Fair Value, Amount Offset Against Collateral [Abstract]
Derivative Asset, Fair Value, Gross Asset	38,836	$ 109,549
Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash, Offset Against Derivative Asset	0	0
Total derivative assets	38,836	109,549
Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Security Not Offset	(34,329)	(82,206)
Derivative Asset, Subject to Master Netting Arrangement, Collateral, Obligation to Return Cash Not Offset	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	4,507	27,343
Derivative Liability, Fair Value, Amount Offset Against Collateral [Abstract]
Derivative Liability, Fair Value, Gross Liability	389,931	223,837
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Offset	0	0
Total derivative liabilities	389,931	223,837
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Security Not Offset	(34,329)	(82,206)
Derivative Liability, Subject to Master Netting Arrangement, Collateral, Right to Reclaim Cash Not Offset	(3,593)	(84)
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 352,009	$ 141,547

Accounting for Derivative Ins_5

Accounting for Derivative Instruments and Hedging Activities (Schedule of Amounts Recognized in Statement of Income) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Derivative Instruments, (Loss) Gain [Line Items]
Unrealized (gain) loss on derivative instruments, net	$ 33,911	$ (284,495)	$ 261,177
Electricity, US Regulated [Member]
Derivative Instruments, (Loss) Gain [Line Items]
Posted Collateral	7,800
Electric Portfolio
Derivative Instruments, (Loss) Gain [Line Items]
Posted Collateral	12,915	12,429
Unrealized gain (loss) on derivative instruments, net		(17,300)	147,100
Electric Portfolio | Credit Rating
Derivative Instruments, (Loss) Gain [Line Items]
Posted Collateral	0	0
Not Designated as Hedging Instrument
Derivative Instruments, (Loss) Gain [Line Items]
Unrealized (gain) loss on derivative instruments, net	(127,836)	(167,429)	440,644
Not Designated as Hedging Instrument | Commodity Contract [Member] | Electric Generation Fuel
Derivative Instruments, (Loss) Gain [Line Items]
Unrealized (gain) loss on derivative instruments, net	(85,476)	47,930	158,550
Not Designated as Hedging Instrument | Commodity Contract [Member] | Purchased Electricity
Derivative Instruments, (Loss) Gain [Line Items]
Unrealized (gain) loss on derivative instruments, net	(76,271)	69,136	20,917
Not Designated as Hedging Instrument | Electric Generation Fuel | Unrealized (Gain) Loss on Derivative Instruments, Net
Derivative Instruments, (Loss) Gain [Line Items]
Unrealized (gain) loss on derivative instruments, net	53,541	(155,774)	61,761
Not Designated as Hedging Instrument | Electricity, US Regulated [Member] | Unrealized (Gain) Loss on Derivative Instruments, Net
Derivative Instruments, (Loss) Gain [Line Items]
Unrealized (gain) loss on derivative instruments, net	$ (19,630)	$ (128,721)	$ 199,416

Accounting for Derivative Ins_6

Accounting for Derivative Instruments and Hedging Activities (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	$ (173,719)	$ 31,113	$ 115,951	$ (44,872)
Fair Value, Net Derivative Asset (Liability), Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Unrealized (gain) loss on derivative instruments, net
Included in earnings	$ (27,262)	(56,656)	180,533
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Regulatory Assets (Liabilities)	(209,845)	4,906	301
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	30,455	(33,475)	(20,603)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	$ 1,820	387	592
Subsidiaries [Member]
Derivative [Line Items]
Hedging strategy number of years extended	3 years
Subsidiaries [Member] | Energy Dedging Activities | Letter of Credit
Derivative [Line Items]
Current borrowing capacity of line of credit	$ 6,600
Natural Gas Portfolio
Derivative [Line Items]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	1,391	3,851	(127)	(2,120)
Included in earnings	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Regulatory Assets (Liabilities)	1,284	4,906	301
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	(4,418)	(1,098)	1,369
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	674	170	323
Electric Portfolio
Derivative [Line Items]
Posted Collateral	12,915	12,429
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs	(175,110)	27,262	116,078	$ (42,752)
Included in earnings	(27,262)	(56,656)	180,533
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Regulatory Assets (Liabilities)	(211,129)	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	34,873	(32,377)	(21,972)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	1,146	217	$ 269
Electricity, US Regulated [Member]
Derivative [Line Items]
Posted Collateral	7,800
Natural Gas, US Regulated [Member]
Derivative [Line Items]
Posted Collateral	$ 0
External Credit Rating, Investment Grade [Member]
Derivative [Line Items]
Percentage of derivatives with credit risk exposure	99.80%
External Credit Rating, Noninvestment Grade [Member]
Derivative [Line Items]
Percentage of derivatives with credit risk exposure	0.20%
Credit Rating | Electric Portfolio
Derivative [Line Items]
Posted Collateral	$ 0	$ 0

Accounting for Derivative Ins_7

Accounting for Derivative Instruments and Hedging Activities (Schedule of Contractual Contingent Liability Positions) (Details) - Electric Portfolio - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Derivative [Line Items]
Fair Value Liability	$ 236,929	$ 66,895
Posted Collateral	12,915	12,429
Contingent Collateral	179,532	13,384
Forward Value of Contract [Member]
Derivative [Line Items]
Fair Value Liability	19,905	84
Posted Collateral	12,915	12,429
Requested Credit for Adequate Assurance
Derivative [Line Items]
Fair Value Liability	37,492	53,427
Posted Collateral	0	0
Contingent Collateral	0	0
Credit Rating
Derivative [Line Items]
Fair Value Liability	179,532	13,384
Posted Collateral	0	0
Contingent Collateral	$ 179,532	$ 13,384

Fair Value Measurements - Debt

Fair Value Measurements - Debt at Carrying and Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Carrying Amount | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Notes Receivable, Fair Value Disclosure	$ 45,400	$ 44,600
Carrying Amount | Income Approach Valuation Technique | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unamortized Debt Issuance Expense	21,300	21,000
Long-term Debt, Fixed Rate, Net of Discount, Fair Value Disclosure	7,423,919	7,036,642
Total | Income Approach Valuation Technique | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fixed Rate, Net of Discount, Fair Value Disclosure	6,966,211	6,855,503
Subsidiaries [Member] | Carrying Amount | Income Approach Valuation Technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities, Fair Value Disclosure	5,961,025	5,184,047
Subsidiaries [Member] | Carrying Amount | Income Approach Valuation Technique | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unamortized Debt Issuance Expense	22,100	21,200
Long-term Debt, Fixed Rate, Net of Discount, Fair Value Disclosure	5,961,025	5,184,047
Subsidiaries [Member] | Total | Income Approach Valuation Technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities, Fair Value Disclosure	5,492,999	5,007,483
Subsidiaries [Member] | Total | Income Approach Valuation Technique | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Fixed Rate, Net of Discount, Fair Value Disclosure	5,492,999	5,007,483
Parent Company [Member] | Carrying Amount | Income Approach Valuation Technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities, Fair Value Disclosure	7,423,919	7,036,642
Parent Company [Member] | Total | Income Approach Valuation Technique
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Excluding Current Maturities, Fair Value Disclosure	$ 6,966,211	$ 6,855,503

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	$ 38,800
Derivative Liability	389,900
Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	38,836	$ 109,549
Derivative Liability	462,980	392,716
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	26,965	53,901
Derivative Liability	277,391	368,181
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	11,871	55,648
Derivative Liability	185,589	24,535
Electric Portfolio | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	35,341	93,028
Derivative Liability	319,506	126,939
Electric Portfolio | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	25,236	42,254
Derivative Liability	134,292	103,427
Electric Portfolio | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	10,105	50,774
Derivative Liability	185,214	23,512
Natural Gas Portfolio | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	3,495	16,521
Derivative Liability	70,425	96,898
Natural Gas Portfolio | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	1,729	11,647
Derivative Liability	70,050	95,875
Natural Gas Portfolio | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	1,766	4,874
Derivative Liability	375	1,023
Compliance obligation | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Liability	73,049	168,879
Compliance obligation | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Liability	73,049	168,879
Compliance obligation | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Liability	$ 0	$ 0

Fair Value Measurements - Unobs

Fair Value Measurements - Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs, Beginning Balance	$ 31,113	$ 115,951	$ (44,872)
Included in earnings	(27,262)	(56,656)	180,533
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Regulatory Assets (Liabilities)	(209,845)	4,906	301
Settlements	30,455	(33,475)	(20,603)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	1,820	387	592
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs, Ending Balance	(173,719)	31,113	115,951
Electric Portfolio
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs, Beginning Balance	27,262	116,078	(42,752)
Included in earnings	(27,262)	(56,656)	180,533
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Regulatory Assets (Liabilities)	(211,129)	0	0
Settlements	34,873	(32,377)	(21,972)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	1,146	217	269
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs, Ending Balance	(175,110)	27,262	116,078
Unrealized gain (loss) on derivative instruments, net		(17,300)	147,100
Natural Gas Portfolio
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs, Beginning Balance	3,851	(127)	(2,120)
Included in earnings	0	0	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Regulatory Assets (Liabilities)	1,284	4,906	301
Settlements	(4,418)	(1,098)	1,369
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3	0	0	0
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers out of Level 3	674	170	323
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs, Ending Balance	$ 1,391	$ 3,851	$ (127)

Fair Value Measurements - Forwa

Fair Value Measurements - Forward Price Ranges (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	$ 38,800
Derivative Liability	$ 389,900
Fair Value measurement, sensitivity analysis, hypothetical increase or decrease of market prices, result on fair value, percent	10%
Fair Value Measurements, Sensitivity Analysis, Hypothetical Increase or Decrease of Market Prices, Result on Fair Value	$ 57,800
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	38,836	$ 109,549
Derivative Liability	462,980	392,716
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	11,871	55,648
Derivative Liability	185,589	24,535
Natural Gas Portfolio | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	3,495	16,521
Derivative Liability	70,425	96,898
Natural Gas Portfolio | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	1,766	4,874
Derivative Liability	375	1,023
Natural Gas Portfolio | Parent Company [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	1,767
Derivative Liability	376
Electric Portfolio | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	35,341	93,028
Derivative Liability	319,506	126,939
Electric Portfolio | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	10,105	50,774
Derivative Liability	185,214	$ 23,512
Electric Portfolio | Parent Company [Member] | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	10,104
Derivative Liability	$ 185,214

Fair Value Measurements - Valua

Fair Value Measurements - Valuations (Details)	12 Months Ended
	Dec. 31, 2024 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Impairment of Intangible Assets, Finite-Lived	$ 0

Fair Value Measurements - Uno_2

Fair Value Measurements - Unobservable Input (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) $ / MMBTU $ / MWh	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	$ 38,800
Derivative Liability	389,900
Fair Value Measurements, Sensitivity Analysis, Hypothetical Increase or Decrease of Market Prices, Result on Fair Value	$ 57,800
Fair Value measurement, sensitivity analysis, hypothetical increase or decrease of market prices, result on fair value, percent	10%
Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	$ 38,836	$ 109,549
Derivative Liability	462,980	392,716
Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	11,871	55,648
Derivative Liability	185,589	24,535
Electric Portfolio | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	35,341	93,028
Derivative Liability	319,506	126,939
Electric Portfolio | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	10,105	50,774
Derivative Liability	185,214	23,512
Natural Gas Portfolio | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	3,495	16,521
Derivative Liability	70,425	96,898
Natural Gas Portfolio | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	1,766	4,874
Derivative Liability	375	1,023
Parent Company [Member] | Electric Portfolio | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	10,104
Derivative Liability	185,214
Parent Company [Member] | Natural Gas Portfolio | Fair Value, Inputs, Level 3 [Member] | Fair Value, Measurements, Recurring
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Derivative Asset	1,767
Derivative Liability	376
Firm Storage and Peaking Service [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Purchase Commitment, Demand Charges	125,000	137,600	$ 138,300
Combustion turbines
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Long-term Purchase Commitment, Demand Charges	$ 71,100	$ 60,500	$ 53,900
Minimum | Income Approach Valuation Technique | Electric Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Power prices (per MWh) | $ / MWh	13.82
Minimum | Income Approach Valuation Technique | Natural Gas Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Price Per Millions of BTU | $ / MMBTU	2.66
Maximum | Income Approach Valuation Technique | Electric Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Power prices (per MWh) | $ / MWh	138.94
Maximum | Income Approach Valuation Technique | Natural Gas Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Price Per Millions of BTU | $ / MMBTU	4.17
Weighted Average | Income Approach Valuation Technique | Electric Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Power prices (per MWh) | $ / MWh	64.59
Weighted Average | Income Approach Valuation Technique | Natural Gas Portfolio
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value Inputs, Price Per Millions of BTU | $ / MMBTU	3.66

Employee Investment Plans - Nar

Employee Investment Plans - Narrative (Details) - Subsidiaries [Member] - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Defined Contribution Plan Disclosure [Line Items]
Employer discretionary contribution amount	$ 31,700,000	$ 28,900,000	$ 25,200,000
Employer matching contribution, percent	4.50%
Maximum annual contribution per employee, percent	6%
employer contribution [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent	4%
Collective Bargaining Arrangement Member [Member] | employer contribution [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent	4%
Cash Balance Formula | Collective Bargaining Arrangement Member [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent	100%
Maximum annual contribution per employee, percent	6%
Employer additional contribution of base pay, percentage	1%
Final Average Earnings Formula | Collective Bargaining Arrangement Member [Member]
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent	55%
Maximum annual contribution per employee, percent	6%
Second 3 Percent
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent	50%
Maximum annual contribution per employee, percent	3%
First 3 Percent
Defined Contribution Plan Disclosure [Line Items]
Employer matching contribution, percent	100%
Maximum annual contribution per employee, percent	3%

Retirement Benefits - Change in

Retirement Benefits - Change in Net Benefit Obligation and Fair Value (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Other Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of period	$ 8,597	$ 9,015
Amendments	34	78
Service cost	197	184
Interest cost	406	439
Actuarial loss (gain)	(194)	(52)
Benefits paid	(792)	(1,067)
Administrative expense	0	0
Benefit obligation at end of period*	8,248	8,597
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	5,085	5,190
Actual return on plan assets	313	543
Employer contribution	179	419
Benefits paid	(792)	(1,067)
Administrative expense	0	0
Fair value of plan assets at end of period	4,785	5,085
Funded status at end of period	(3,463)	(3,512)
Nonqualified Plan | Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of period	26,824	32,046
Amendments	0	0
Service cost	0	143
Interest cost	1,370	1,589
Actuarial loss (gain)	(1,752)	(661)
Benefits paid	(1,978)	(3,521)
Administrative expense	0	0
Benefit obligation at end of period*	24,464	26,824
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	0	0
Actual return on plan assets	0	0
Employer contribution	1,978	3,521
Benefits paid	(1,978)	(3,521)
Administrative expense	0	0
Fair value of plan assets at end of period	0	0
Funded status at end of period	(24,464)	(26,824)
Qualified Plan | Pension Plan [Member]
Defined Benefit Plan, Change in Benefit Obligation [Roll Forward]
Benefit obligation at beginning of period	609,103	589,278
Amendments	0	0
Service cost	18,616	18,530
Interest cost	31,152	32,375
Actuarial loss (gain)	(38,952)	8,469
Benefits paid	(41,583)	(38,258)
Administrative expense	(1,350)	(1,291)
Benefit obligation at end of period*	576,986	609,103
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets at beginning of period	746,011	658,533
Actual return on plan assets	51,509	109,028
Employer contribution	18,000	18,000
Benefits paid	(41,583)	(38,258)
Administrative expense	(1,247)	(1,292)
Fair value of plan assets at end of period	772,690	746,011
Funded status at end of period	$ 195,704	$ 136,908

Retirement Benefits - Amounts R

Retirement Benefits - Amounts Recognized (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 8,248	$ 8,597	$ 9,015
Accumulated benefit obligation	8,109	8,487
Fair value of plan assets	4,785	5,085	5,190
Defined Benefit Plan, Amounts Recognized in Statement of Financial Position Consist of: [Abstract]
Noncurrent assets	0	0
Current liabilities	(237)	(225)
Noncurrent liabilities	(3,226)	(3,287)
Net assets (liabilities)	(3,463)	(3,512)
Parent Company [Member] | Other Pension Plan [Member]
Defined Benefit Plan, Amounts Recognized in Accumulated Other Comprehensive Income Consist of: [Abstract]
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	(2,132)	(2,052)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	311	310
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, Total	(1,821)	(1,742)
Subsidiaries [Member] | Other Pension Plan [Member]
Defined Benefit Plan, Amounts Recognized in Accumulated Other Comprehensive Income Consist of: [Abstract]
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	(2,204)	(2,124)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	311	310
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, Total	(1,893)	(1,814)
Nonqualified Plan | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	24,464	26,824	32,046
Accumulated benefit obligation	24,464	26,824
Fair value of plan assets	0	0	0
Defined Benefit Plan, Amounts Recognized in Statement of Financial Position Consist of: [Abstract]
Noncurrent assets	0	0
Current liabilities	(6,759)	(1,978)
Noncurrent liabilities	(17,705)	(24,846)
Net assets (liabilities)	(24,464)	(26,824)
Nonqualified Plan | Parent Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Amounts Recognized in Accumulated Other Comprehensive Income Consist of: [Abstract]
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	(3,579)	(1,870)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	0	0
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, Total	(3,579)	(1,870)
Nonqualified Plan | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan, Amounts Recognized in Accumulated Other Comprehensive Income Consist of: [Abstract]
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	(3,342)	(1,613)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	0	0
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, Total	(3,342)	(1,613)
Qualified Plan | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	576,986	609,103	589,278
Accumulated benefit obligation	571,306	601,981
Fair value of plan assets	772,690	746,011	$ 658,533
Defined Benefit Plan, Amounts Recognized in Statement of Financial Position Consist of: [Abstract]
Noncurrent assets	195,704	136,908
Current liabilities	0	0
Noncurrent liabilities	0	0
Net assets (liabilities)	195,704	136,908
Qualified Plan | Parent Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Amounts Recognized in Accumulated Other Comprehensive Income Consist of: [Abstract]
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	(49,242)	(16,257)
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	0	0
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, Total	(49,242)	(16,257)
Qualified Plan | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan, Amounts Recognized in Accumulated Other Comprehensive Income Consist of: [Abstract]
Accumulated Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), after Tax	39,183	74,851
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), after Tax	0	0
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax, Total	$ 39,183	$ 74,851

Retirement Benefits - Net Perio

Retirement Benefits - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	$ 197	$ 184
Interest cost	406	439
Parent Company [Member] | Other Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	197	184	$ 217
Interest cost	406	439	311
Expected return on plan assets	(288)	(297)	(379)
Amortization of prior service cost (credit)	33	28	22
Amortization of net loss (gain)	(139)	(210)	(29)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total	209	144	142
Subsidiaries [Member] | Other Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	197	184	217
Interest cost	406	439	311
Expected return on plan assets	(288)	(297)	(379)
Amortization of prior service cost (credit)	33	28	22
Amortization of net loss (gain)	(139)	(230)	(35)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total	209	124	136
Nonqualified Plan | Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	143
Interest cost	1,370	1,589
Nonqualified Plan | Parent Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	143	557
Interest cost	1,370	1,589	1,253
Expected return on plan assets	0	0	0
Amortization of prior service cost (credit)	0	144	289
Amortization of net loss (gain)	(42)	0	2,471
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total	1,328	1,876	4,570
Nonqualified Plan | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	0	143	557
Interest cost	1,370	1,589	1,253
Expected return on plan assets	0	0	0
Amortization of prior service cost (credit)	0	144	289
Amortization of net loss (gain)	(22)	44	2,648
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total	1,348	1,920	4,747
Qualified Plan | Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	18,616	18,530
Interest cost	31,152	32,375
Qualified Plan | Parent Company [Member] | Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	18,616	18,530	26,351
Interest cost	31,152	32,375	24,263
Expected return on plan assets	(54,896)	(50,641)	(51,014)
Amortization of prior service cost (credit)	0	0	0
Amortization of net loss (gain)	(2,684)	(2,447)	6,381
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total	(7,812)	(2,183)	5,981
Qualified Plan | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) [Abstract]
Service cost	18,616	18,530	26,351
Interest cost	31,152	32,375	24,263
Expected return on plan assets	(54,897)	(50,641)	(51,016)
Amortization of prior service cost (credit)	0	0	0
Amortization of net loss (gain)	0	0	15,080
Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Total	$ (5,129)	$ 264	$ 14,678

Retirement Benefits - Benefit O

Retirement Benefits - Benefit Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution, percent	4.50%
Defined Contribution Plan, Interest Credit	4%
Subsidiaries [Member] | employer contribution [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution, percent	4%
Subsidiaries [Member] | employer contribution [Member] | Collective Bargaining Arrangement Member [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution, percent	4%
Subsidiaries [Member] | employer contribution [Member] | Collective Bargaining Arrangement Member [Member] | UA represented [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution, percent	4%
Subsidiaries [Member] | employer contribution [Member] | Collective Bargaining Arrangement Member [Member] | IBEW represented [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer matching contribution, percent	4%
Other Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	$ (219)	$ (298)
Amortization of net (loss) gain	139	210
Settlements, mergers, sales, and closures	0	0
Prior service cost (credit)	34	79
Amortization of prior service (cost) credit	(33)	(28)
Total change in other comprehensive income for year	(79)	(37)
Curtailment loss / (gain)	0	0
Actuarial loss (gain)	(194)	(52)
Other Pension Plan [Member] | Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	(219)	(298)
Amortization of net (loss) gain	139	230
Settlements, mergers, sales, and closures	0	0
Prior service cost (credit)	34	79
Amortization of prior service (cost) credit	(33)	(28)
Total change in other comprehensive income for year	(79)	(17)
Qualified Plan | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	(44,439)	(49,917)
Amortization of net (loss) gain	2,684	2,447
Settlements, mergers, sales, and closures	0	0
Prior service cost (credit)	0	0
Amortization of prior service (cost) credit	0	0
Total change in other comprehensive income for year	(41,755)	(47,470)
Curtailment loss / (gain)	0	0
Actuarial loss (gain)	(38,952)	8,469
Qualified Plan | Pension Plan [Member] | Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	(44,438)	(49,916)
Amortization of net (loss) gain	0	0
Settlements, mergers, sales, and closures	0	0
Prior service cost (credit)	0	0
Amortization of prior service (cost) credit	0	0
Total change in other comprehensive income for year	(44,438)	(49,916)
Nonqualified Plan | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	(1,751)	(3,433)
Amortization of net (loss) gain	42	0
Settlements, mergers, sales, and closures	0	(145)
Prior service cost (credit)	0	0
Amortization of prior service (cost) credit	0	(144)
Total change in other comprehensive income for year	(1,709)	(3,722)
Curtailment loss / (gain)	0	2,772
Actuarial loss (gain)	(1,752)	(661)
Nonqualified Plan | Pension Plan [Member] | Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net loss (gain)	(1,751)	(3,433)
Amortization of net (loss) gain	22	(44)
Settlements, mergers, sales, and closures	0	(145)
Prior service cost (credit)	0	0
Amortization of prior service (cost) credit	0	(144)
Total change in other comprehensive income for year	$ (1,729)	$ (3,766)

Retirement Benefits - Textuals

Retirement Benefits - Textuals (Details) $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($)
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Five-year smoothing of asset gains (losses)	5 years
Subsidiaries [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Contribution Plan, Interest Credit	4%
Qualified Plan | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated Future Employer Contributions in Current Fiscal Year	$ 18
Nonqualified Plan | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated Future Employer Contributions in Current Fiscal Year	6.8
Other Pension Plan [Member] | Subsidiaries [Member] | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated Future Employer Contributions in Current Fiscal Year	$ 0.2

Retirement Benefits - Assumptio

Retirement Benefits - Assumptions (Details)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	5.80%	5.30%	5.60%
Rate of compensation increase	4.50%	4.50%	4.50%
Benefit Cost Assumptions:
Discount rate	5.30%	5.60%	3%
Return on plan assets	7%	7%	7%
Rate of compensation increase	4.50%	4.50%	4.50%
Nonqualified Plan | Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	5.80%	5.30%	5.60%
Rate of compensation increase	4.50%	4.50%	4.50%
Benefit Cost Assumptions:
Discount rate	5.30%	5.60%	3%
Return on plan assets	0%	0%	0%
Rate of compensation increase	4.50%	4.50%	4.50%
Qualified Plan | Pension Plan [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount rate	5.80%	5.30%	5.60%
Rate of compensation increase	4.50%	4.50%	4.50%
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Weighted-Average Interest Crediting Rate	4%	4%	4%
Benefit Cost Assumptions:
Discount rate	5.30%	5.60%	3%
Return on plan assets	7%	6.75%	6.50%
Rate of compensation increase	4.50%	4.50%	4.50%
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Weighted-Average Interest Crediting Rate	4%	4%	4%

Retirement Benefits - Future Be

Retirement Benefits - Future Benefit Payments (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Other Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
2025	$ 870
2026	847
2027	838
2028	834
2029	837
2030-2034	3,491
Qualified Plan | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
2025	43,800
2026	44,700
2027	45,400
2028	46,100
2029	47,100
2030-2034	242,200
Nonqualified Plan | Pension Plan [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
2025	6,759
2026	2,263
2027	4,222
2028	1,630
2029	1,559
2030-2034	$ 7,295

Retirement Benefits - Plan Asse

Retirement Benefits - Plan Asset Allocation (Details)	Dec. 31, 2024
Domestic Large Cap Equity Investments [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	28%
Domestic Small Cap Equity Investments [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	8%
Foreign Equity Funds [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	24%
Fixed Income Securities [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	40%
Cash and cash equivalents
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	0%
Minimum | Domestic Large Cap Equity Investments [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	22%
Minimum | Foreign Equity Funds [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	10%
Minimum | Fixed Income Securities [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	30%
Maximum | Domestic Large Cap Equity Investments [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	35%
Maximum | Domestic Small Cap Equity Investments [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	12%
Maximum | Foreign Equity Funds [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	30%
Maximum | Fixed Income Securities [Member]
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	50%
Maximum | Cash and cash equivalents
Defined Benefit Plan and Other Postretirement Benefit Plans Table Text Block [Line Items]
Target Allocation	5%

Retirement Benefits - Recurring

Retirement Benefits - Recurring Fair Value Measures (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 4,785	$ 5,085	$ 5,190
Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,785	5,085
Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	772,690	746,011
Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,785	5,085
Mutual Funds | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Funds | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,785	5,085
Mutual Funds | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Funds | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Other Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	4,785	5,085
US Treasury and Government [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	100,126	73,243
US Treasury and Government [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	13,172	12,709
US Treasury and Government [Member] | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
US Treasury and Government [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	113,298	85,952
Cash and cash equivalents | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	5,263	2,846
Cash and cash equivalents | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(6,323)	236
Cash and cash equivalents | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Cash and cash equivalents | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(1,060)	3,082
Equity Investments [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	311,808	301,274
Equity Investments [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	39,859	36,842
Equity Investments [Member] | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	421,023	407,895
Net Receivables [Member] | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Net Receivables [Member] | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Net Receivables [Member] | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(50,454)	(29,974)
Net Receivables [Member] | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	(50,454)	(29,974)
Partnership/Jointed Ventures | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Partnership/Jointed Ventures | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Partnership/Jointed Ventures | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	90,308	91,845
Partnership/Jointed Ventures | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	90,308	91,845
Collective Investment Funds | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Collective Investment Funds | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Collective Investment Funds | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	321,937	297,780
Collective Investment Funds | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	321,937	297,780
Other Security Investments | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other Security Investments | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Other Security Investments | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,045	128
Other Security Investments | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2,045	128
Mutual Fund | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75,186	81,130
Mutual Fund | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Fund | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Fund | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	75,186	81,130
Corporate Bond Securities - Foreign | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate Bond Securities - Foreign | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15,004	8,829
Corporate Bond Securities - Foreign | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate Bond Securities - Foreign | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	15,004	8,829
Corporate Bond Securities - US | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate Bond Securities - US | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17,807	14,787
Corporate Bond Securities - US | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Corporate Bond Securities - US | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	17,807	14,787
Common Stock - US | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	117,183	130,288
Common Stock - US | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	199	281
Common Stock - US | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock - US | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	117,382	130,569
Common Stock - Foreign | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,050	13,767
Common Stock - Foreign | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock - Foreign | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Common Stock - Foreign | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	14,050	13,767
Mutual Fund with no published price | Fair Value, Inputs, Level 1 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Fund with no published price | Fair Value, Inputs, Level 2 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Mutual Fund with no published price | Fair Value Measured at Net Asset Value Per Share [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	57,187	48,116
Mutual Fund with no published price | Fair Value, Inputs, Level 1, 2 and 3 [Member] | Fair Value, Measurements, Recurring | Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 57,187	$ 48,116

Income Taxes - Components of In

Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosures [Line Items]
Current Federal Tax Expense (Benefit)	$ 31,101	$ 66,086	$ 41,198
Current State and Local Tax Expense (Benefit)	364	1,317	628
Deferred Federal Income Tax Expense (Benefit)	(875)	(94,860)	17,866
Deferred State and Local Income Tax Expense (Benefit)	133	23	6
Total income tax expense	$ 30,723	(27,434)	59,698
Valuation Allowance, Commentary	no
Subsidiaries [Member]
Income Tax Disclosures [Line Items]
Current Federal Tax Expense (Benefit)	$ 61,924	112,168	81,597
Current State and Local Tax Expense (Benefit)	889	1,626	869
Deferred Federal Income Tax Expense (Benefit)	(10,226)	(120,397)	(2,171)
Deferred State and Local Income Tax Expense (Benefit)	0	0	0
Total income tax expense	$ 52,587	$ (6,603)	$ 80,295

Income Taxes - Deferred Income

Income Taxes - Deferred Income Taxes (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Deferred Tax Liabilities, Gross
Deferred Tax Liabilities, Property, Plant and Equipment	$ 1,768,358	$ 1,799,505
Deferred Tax Liabilities, Other	466,317	407,842
Deferred Tax Liabilities, Gross, Total	2,234,675	2,207,347
Deferred Tax Assets, Gross
Deferred Tax Assets, Operating Loss Carryforwards	(201,562)	(210,238)
Deferred Tax Assets, Net Regulatory Liability for Income Taxes	(721,907)	(760,961)
Deferred Tax Assets, Other	(313,526)	(285,919)
Deferred Tax Assets, Gross	(1,236,995)	(1,257,118)
Deferred Tax Liabilities, Net, Total	997,680	950,229
Subsidiaries [Member]
Deferred Tax Liabilities, Gross
Deferred Tax Liabilities, Property, Plant and Equipment	1,763,456	1,796,476
Deferred Tax Liabilities, Other	382,968	319,328
Deferred Tax Liabilities, Gross, Total	2,146,424	2,115,804
Deferred Tax Assets, Gross
Deferred Tax Assets, Net Regulatory Liability for Income Taxes	(722,558)	(761,621)
Deferred Tax Assets, Other	(306,374)	(275,336)
Deferred Tax Assets, Gross	(1,028,932)	(1,036,957)
Deferred Tax Liabilities, Net, Total	$ 1,117,492	$ 1,078,847

Income Taxes - Balance Sheet Lo

Income Taxes - Balance Sheet Location (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	$ 0	$ (8,689)	$ (13,722)
Subsidiaries [Member]
Income Tax Disclosures [Line Items]
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	(8,689)	(13,722)
ARAM [Member]
Income Tax Disclosures [Line Items]
Deferred Other Tax Expense (Benefit)	$ 29,800	$ 27,800	$ 27,200

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ 63,256	$ 5,524	$ 99,549
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Amount	(29,712)	(23,806)	(23,028)
Income Tax Reconciliation, AFUDC (net)	(5,704)	(4,017)	(3,567)
Income Tax Reconciliation, Executive Compensation	2,209	1,544	1,821
Income Tax Reconciliation, Treasury Grant	(797)	(750)	(5,717)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	(8,689)	(13,722)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	393	1,070	505
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	1,078	1,690	3,857
Total income tax expense	$ 30,723	$ (27,434)	$ 59,698
Effective Income Tax Rate Reconciliation, Percent	10.10%	(104.30%)	12.60%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent	0%	(33.00%)	(2.90%)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	0.10%	4.10%	0.10%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	0.40%	6.40%	0.90%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21%	21%	21%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Percent	(9.90%)	(90.50%)	(4.90%)
Income Tax Reconciliation, AFUDC (net), Percentage	(1.90%)	(15.30%)	(0.80%)
Income Tax Reconciliation, Executive Compensation, Percentage	0.70%	5.90%	0.40%
Income Tax Reconciliation, Treasury Grant, Percentage	(0.30%)	(2.90%)	(1.20%)
Subsidiaries [Member]
Operating Loss Carryforwards [Line Items]
Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount	$ 84,835	$ 26,136	$ 119,962
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Amount	(29,712)	(23,806)	(23,028)
Income Tax Reconciliation, AFUDC (net)	(5,704)	(4,017)	(3,567)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount	0	(8,689)	(13,722)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	702	1,291	689
Effective Income Tax Rate Reconciliation, Other Adjustments, Amount	2,466	2,482	(39)
Total income tax expense	$ 52,587	$ (6,603)	$ 80,295
Effective Income Tax Rate Reconciliation, Percent	13%	(5.30%)	14.10%
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Percent	0%	(7.00%)	(2.40%)
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	0.20%	1%	0.10%
Effective Income Tax Rate Reconciliation, Other Adjustments, Percent	0.60%	2%	0%
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21%	21%	21%
Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depreciation and Amortization, Percent	(7.40%)	(19.10%)	(4.00%)
Income Tax Reconciliation, AFUDC (net), Percentage	(1.40%)	(3.20%)	(0.60%)

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Operating Loss Carryforwards [Line Items]
Valuation Allowance, Commentary	no
Unrecognized Tax Benefits	$ 0	$ 0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0	0
ARAM [Member]
Operating Loss Carryforwards [Line Items]
Deferred Other Tax Expense (Benefit)	$ 29,800,000	$ 27,800,000	$ 27,200,000

Litigation (Details)

Litigation (Details) - Subsidiaries [Member]	Dec. 31, 2024
Colstrip Unit 4 [Member]
Jointly Owned Utility Plant Interests
Company’s Ownership Share	25%
Colstrip Units 1 & 2
Jointly Owned Utility Plant Interests
Company’s Ownership Share	50%

Commitments and Contingencies_2

Commitments and Contingencies (Details)			1 Months Ended					12 Months Ended
	Dec. 31, 2023	Dec. 13, 2001	Jun. 30, 2024	Apr. 30, 2024	Mar. 31, 2021	Mar. 31, 2017	Feb. 28, 2006	Dec. 31, 2024 USD ($) MWh contract MW	Dec. 31, 2023 USD ($) MWh	Dec. 31, 2022 USD ($) MWh
Long-term Purchase Commitment [Line Items]
Number of Public Utility Districts with long term purchase agreements | contract								3
Contract expenses								$ 211,800,000	$ 174,385,000	$ 149,575,000
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								10.90%
Long-term Contract for Purchase of Electric Power, Capacity | MW								1,163
Long-term Contract for Purchase of Electric Power, Estimated Annual Cost								$ 350,035,000
Long-term Contract for Purchase of Electric Power, Annual Minimum Debt Service Payment Required								27,285,000
Long-term Contract for Purchase of Electric Power, Interest Included in Contract Charges								7,712,000
Long-term Contract for Purchase of Electric Power, Amount of Long-term Debt or Lease Obligation Outstanding								139,017,000
Payment Obligations for Power Purchases
2025								1,050,859,000
2026								652,207,000
2027								572,676,000
2028								599,406,000
2029								519,225,000
Thereafter								7,787,791,000
Total								$ 11,182,164,000
Total energy obtained during period under purchased power contracts (MWh) | MWh								14.6	14.7	15.3
Cost incurred during period to provide energy under purchased power contracts								$ 1,006,300,000	$ 851,600,000	$ 892,700,000
Daily take obligation under long-term service contract (percent)								100%
Daily delivery obligation under long-term service contract (percent)								100%
Average cost of Company's energy output (US$ per kWh)								$ 0.067
Natural Gas [Member]
Payment Obligations for Power Purchases
2025								517,802,000
2026								429,749,000
2027								277,306,000
2028								180,565,000
2029								79,714,000
Thereafter								0
Total								1,485,136,000
Firm Transportation Service [Member]
Payment Obligations for Power Purchases
2025								167,274,000
2026								165,151,000
2027								166,716,000
2028								163,261,000
2029								144,884,000
Thereafter								669,602,000
Total								1,476,888,000
Firm Storage and Peaking Service [Member]
Payment Obligations for Power Purchases
2025								9,350,000
2026								8,476,000
2027								8,189,000
2028								2,678,000
2029								837,000
Thereafter								4,946,000
Total								34,476,000
Long-term Purchase Commitment, Demand Charges								125,000,000	137,600,000	138,300,000
Combustion turbines
Payment Obligations for Power Purchases
Long-term Purchase Commitment, Demand Charges								71,100,000	$ 60,500,000	$ 53,900,000
Energy production service contracts
Payment Obligations for Power Purchases
2025								36,920,000
2026								40,184,000
2027								40,987,000
2028								41,823,000
2029								42,639,000
Thereafter								60,494,000
Total								263,047,000
Electric Portfolio
Payment Obligations for Power Purchases
2025								474,683,000
2026								255,973,000
2027								258,701,000
2028								304,056,000
2029								291,040,000
Thereafter								3,709,279,000
Total								5,293,732,000
Firm natural gas supply
Payment Obligations for Power Purchases
2025								694,426,000
2026								603,376,000
2027								452,211,000
2028								346,504,000
2029								225,435,000
Thereafter								674,548,000
Total								2,996,500,000
Colombia River Projects [Member]
Payment Obligations for Power Purchases
2025								350,035,000
2026								238,243,000
2027								226,541,000
2028								238,331,000
2029								171,203,000
Thereafter								3,563,272,000
Colombia River Projects [Member]
Payment Obligations for Power Purchases
Total								4,787,625,000
Electric Wholesale Market Transactions
Payment Obligations for Power Purchases
2025								226,141,000
2026								157,991,000
2027								87,434,000
2028								57,019,000
2029								56,982,000
Thereafter								515,240,000
Total								$ 1,100,807,000
Minimum | Combustion turbines
Payment Obligations for Power Purchases
Remaining terms under contract								1 year
Maximum | Combustion turbines
Payment Obligations for Power Purchases
Remaining terms under contract								21 years
Rock Island Project
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								40%
Long-term Contract for Purchase of Electric Power, Capacity | MW								252
Long-term Contract for Purchase of Electric Power, Estimated Annual Cost								$ 85,641,000
Long-term Contract for Purchase of Electric Power, Annual Minimum Debt Service Payment Required								20,499,000
Long-term Contract for Purchase of Electric Power, Interest Included in Contract Charges								5,572,000
Long-term Contract for Purchase of Electric Power, Amount of Long-term Debt or Lease Obligation Outstanding								$ 98,638,000
Rocky Reach Project
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								40%
Long-term Contract for Purchase of Electric Power, Capacity | MW								540
Long-term Contract for Purchase of Electric Power, Estimated Annual Cost								$ 112,077,000
Long-term Contract for Purchase of Electric Power, Annual Minimum Debt Service Payment Required								6,166,000
Long-term Contract for Purchase of Electric Power, Interest Included in Contract Charges								1,808,000
Long-term Contract for Purchase of Electric Power, Amount of Long-term Debt or Lease Obligation Outstanding								$ 32,155,000
Wells Project [Member]
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								18.60%
Long-term Contract for Purchase of Electric Power, Capacity | MW								156
Long-term Contract for Purchase of Electric Power, Estimated Annual Cost								$ 42,883,000
Long-term Contract for Purchase of Electric Power, Annual Minimum Debt Service Payment Required								0
Long-term Contract for Purchase of Electric Power, Interest Included in Contract Charges								0
Long-term Contract for Purchase of Electric Power, Amount of Long-term Debt or Lease Obligation Outstanding								$ 0
Priest Rapids Development
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								9.90%
Long-term Contract for Purchase of Electric Power, Capacity | MW								94
Long-term Contract for Purchase of Electric Power, Estimated Annual Cost								$ 54,717,000
Long-term Contract for Purchase of Electric Power, Annual Minimum Debt Service Payment Required								310,000
Long-term Contract for Purchase of Electric Power, Interest Included in Contract Charges								166,000
Long-term Contract for Purchase of Electric Power, Amount of Long-term Debt or Lease Obligation Outstanding								$ 4,112,000
Wanapum Development
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								9.90%
Long-term Contract for Purchase of Electric Power, Capacity | MW								121
Long-term Contract for Purchase of Electric Power, Estimated Annual Cost								$ 54,717,000
Long-term Contract for Purchase of Electric Power, Annual Minimum Debt Service Payment Required								310,000
Long-term Contract for Purchase of Electric Power, Interest Included in Contract Charges								166,000
Long-term Contract for Purchase of Electric Power, Amount of Long-term Debt or Lease Obligation Outstanding								4,112,000
Subsidiaries [Member]
Payment Obligations for Power Purchases
Loss Contingency Accrual								$ 26,200,000
Subsidiaries [Member] | Rock Island Project
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	25%				5%		25%	5%	5%
Payment Obligations for Power Purchases
Number of Contracts | contract								4
Subsidiaries [Member] | Rocky Reach Project
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased	25%				5%		25%	5%	5%
Payment Obligations for Power Purchases
Number of Contracts | contract								4
Subsidiaries [Member] | Wells Project [Member]
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased					5.50%	13.10%			5.50%
Payment Obligations for Power Purchases
Number of Contracts | contract								3
Subsidiaries [Member] | Wells Project [Member] | Minimum
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								9.50%
Subsidiaries [Member] | Wells Project [Member] | Maximum
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased								18.90%
Subsidiaries [Member] | Priest Rapids Development
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased		0.64%	4.22%	0.88%				4.13%
Payment Obligations for Power Purchases
Number of Contracts | contract								4
Subsidiaries [Member] | Wanapum Development
Long-term Purchase Commitment [Line Items]
Long-term Contract for Purchase of Electric Power, Share of Plant Output Being Purchased		0.64%	4.22%	0.88%				4.13%
Payment Obligations for Power Purchases
Number of Contracts | contract								4

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Related Party Transaction [Line Items]
Related Party Transaction, Amounts of Transaction	$ 0	$ 0	$ 0

Accumulated Other Comprehensi_3

Accumulated Other Comprehensive Income (Loss) Changes in AOCI, net of tax (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	$ 17,539
Accumulated other comprehensive income (loss), net of tax	43,168	$ 17,539
Subsidiaries [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	(58,394)
Accumulated other comprehensive income (loss), net of tax	(30,247)	(58,394)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	17,539	(24,774)	$ (27,432)
Other comprehensive income (loss) before reclassifications	27,866	44,277	(4,559)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(2,237)	(1,964)	7,217
Net current-period other comprehensive income (loss)	25,629	42,313	2,658
Accumulated other comprehensive income (loss), net of tax	43,168	17,539	(24,774)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] | Subsidiaries [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	(54,565)	(98,830)	(108,541)
Other comprehensive income (loss) before reclassifications	27,862	44,277	(4,512)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(101)	(12)	14,223
Net current-period other comprehensive income (loss)	27,761	44,265	9,711
Accumulated other comprehensive income (loss), net of tax	(26,804)	(54,565)	(98,830)
Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	17,539	(24,774)	(27,432)
Other comprehensive income (loss) before reclassifications	27,866	44,277	(4,559)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	(2,237)	(1,964)	7,217
Net current-period other comprehensive income (loss)	25,629	42,313	2,658
Accumulated other comprehensive income (loss), net of tax	43,168	17,539	(24,774)
Comprehensive Income [Member] | Subsidiaries [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	(58,394)	(103,044)	(113,141)
Other comprehensive income (loss) before reclassifications	27,862	44,277	(4,512)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	285	373	14,609
Net current-period other comprehensive income (loss)	28,147	44,650	10,097
Accumulated other comprehensive income (loss), net of tax	(30,247)	(58,394)	(103,044)
Interest Rate Swap [Member] | Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member] | Subsidiaries [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated other comprehensive income (loss), net of tax	(3,829)	(4,214)	(4,600)
Other comprehensive income (loss) before reclassifications	0	0	0
Amounts reclassified from accumulated other comprehensive income (loss), net of tax	386	385	386
Net current-period other comprehensive income (loss)	386	385	386
Accumulated other comprehensive income (loss), net of tax	$ (3,443)	$ (3,829)	$ (4,214)

Accumulated Other Comprehensi_4

Accumulated Other Comprehensive Income (Loss) Reclassifications Out of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Reclassification out of Accumulated Other Comprehensive Income | Parent Company [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Total reclassification for the period	$ 2,237	$ 1,964	$ (7,217)
Reclassification out of Accumulated Other Comprehensive Income | Subsidiaries [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Total reclassification for the period	(285)	(373)	(14,609)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] | Parent Company [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service (cost) credit	(33)	(172)	(311)
Amortization of net (loss) gain	2,865	2,658	(8,824)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	2,832	2,486	(9,135)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax	(595)	(522)	1,918
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax	2,237	1,964	(7,217)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Noncontrolling Interest [Member] | Subsidiaries [Member] | Interest Rate Swap [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	(487)	(488)	(488)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	(101)	(103)	(102)
Total reclassification for the period	(386)	(385)	(386)
Accumulated Defined Benefit Plans Adjustment Attributable to Noncontrolling Interest [Member] | Subsidiaries [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Amortization of prior service (cost) credit	(33)	(172)	(311)
Amortization of net (loss) gain	161	187	(17,693)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, before Tax	128	15	(18,004)
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax	(27)	(3)	3,781
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax	$ 101	$ 12	$ (14,223)

Segment Information (Details)

Segment Information (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($) mi²	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Segment Reporting Information [Line Items]
Regulated and Unregulated Operating Revenue	$ 4,856,215	$ 4,816,574	$ 4,221,162
Depreciation and amortization	787,986	751,335	663,232
Income tax (benefit) expense	30,723	(27,434)	59,698
Non-utility expense and other	46,056	56,515	59,804
Interest Expense, Debt	(432,194)	(381,511)	(347,921)
Net Income (Loss)	265,255	53,740	414,345
Assets	18,960,391	17,732,453	17,187,514
Construction expenditures - excluding equity AFUDC	(1,609,715)	(1,466,565)	(1,004,713)
Natural gas	1,488,570	1,423,276	1,209,636
Reportable Segment, Aggregation before Other Operating Segment
Segment Reporting Information [Line Items]
Regulated and Unregulated Operating Revenue	4,825,231	4,786,618	4,216,173
Depreciation and amortization	781,325	744,629	657,349
Income tax (benefit) expense	52,587	(6,603)	80,295
Non-utility expense and other	21,664	28,658	47,194
Interest Expense, Debt	(321,550)	(285,148)	(256,774)
Net Income (Loss)	346,148	131,059	490,952
Assets	17,026,384	15,771,767	15,200,242
Construction expenditures - excluding equity AFUDC	(1,608,947)	(1,465,925)	(1,000,810)
Other Operating Segment
Segment Reporting Information [Line Items]
Regulated and Unregulated Operating Revenue	30,984	29,956	4,989
Depreciation and amortization	6,661	6,706	5,883
Income tax (benefit) expense	(21,864)	(20,831)	(20,597)
Non-utility expense and other	24,392	27,857	12,610
Interest Expense, Debt	(110,644)	(96,363)	(91,147)
Net Income (Loss)	(80,893)	(77,319)	(76,607)
Assets	1,934,007	1,960,686	1,987,272
Construction expenditures - excluding equity AFUDC	$ (768)	(640)	(3,903)
Subsidiaries [Member]
Segment Reporting Information [Line Items]
Area of service territory (sqmi) | mi²	6,000
Regulated and Unregulated Operating Revenue	$ 4,825,231	4,786,618	4,216,173
Depreciation and amortization	781,325	744,629	657,349
Income tax (benefit) expense	52,587	(6,603)	80,295
Non-utility expense and other	21,664	28,658	47,194
Interest Expense, Debt	(321,550)	(285,148)	(256,774)
Net Income (Loss)	346,148	131,059	490,952
Assets	17,026,384	15,771,767
Construction expenditures - excluding equity AFUDC	(1,608,947)	(1,465,925)	(1,000,810)
Natural gas	1,492,254	1,424,368	1,209,636
Puget LNG [Member]
Segment Reporting Information [Line Items]
Natural gas	$ 3,700	$ 1,100	$ 0

SCHEDULE I CONDENSED FINANCIA_2

SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PUGET ENERGY - Condensed Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Condensed Financial Statements, Captions [Line Items]
Nonutility Expense And Other	$ (46,056)	$ (56,515)	$ (59,804)
Interest expense	(432,194)	(381,511)	(347,921)
Income Tax Expense (Benefit)	(30,723)	27,434	(59,698)
Net income (loss)	265,255	53,740	414,345
Comprehensive income (loss)	290,884	96,053	417,003
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	822,823	1,053,395	769,618
Other	(1,872)	(14,047)	567
Net Cash Provided by (Used in) Investing Activities	(1,607,843)	(1,452,518)	(1,005,280)
Dividends paid	175,861	99,760	16,230
Capital contribution	292,800	0	0
Short-term debt	(219,700)	122,500	301,300
Proceeds from Issuance of Long-term Debt	793,892	396,488	448,075
Redemption of bonds and notes	0	0	450,000
Net Cash Provided by (Used in) Financing Activities	711,146	444,913	301,297
Net increase (decrease) in cash, cash equivalents, and restricted cash	(73,874)	45,790	65,635
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	140,701	214,575	168,785	$ 103,150
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Nonutility Expense And Other	(2,883)	(1,466)	(1,206)
Equity In Net Income (Loss) Of Subsidiaries	334,121	110,719	474,873
Investment Income, Interest	18,439	17,863	8,458
Interest expense	(103,019)	(88,739)	(84,051)
Income Tax Expense (Benefit)	18,597	15,363	16,271
Net income (loss)	265,255	53,740	414,345
Comprehensive income (loss)	290,884	96,053	417,003
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities	96,588	64,506	(10,197)
Adjustments to Additional Paid in Capital, Other	292,800	100,000	50,000
Payments for (Proceeds from) Loans Receivable from Subsidiary	590	9,753	12,176
Net Cash Provided by (Used in) Investing Activities	(293,390)	(109,753)	(62,176)
Dividends paid	175,861	99,760	16,230
Capital contribution	292,800	0	0
Short-term debt	76,900	142,900	84,300
Proceeds from Issuance of Long-term Debt	0	0	448,075
Redemption of bonds and notes	0	0	450,000
Issue costs and others	(2,184)	(2,175)	(1,370)
Net Cash Provided by (Used in) Financing Activities	196,023	45,315	67,515
Net increase (decrease) in cash, cash equivalents, and restricted cash	(779)	68	(4,858)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 817	$ 1,596	$ 1,528	$ 6,386

SCHEDULE I CONDENSED FINANCIA_3

SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PUGET ENERGY - Condensed Balance Sheets (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Other Property And Investments [Abstract]
Goodwill	$ 1,656,513	$ 1,656,513
Current assets:
Cash and Cash Equivalents, at Carrying Value	101,836	148,548
Total current assets	1,408,018	1,432,435
Assets, Noncurrent [Abstract]
Other	310,094	259,291
Total assets	18,960,391	17,732,453	$ 17,187,514
Capitalization, Long-term Debt and Equity [Abstract]
Stockholders' Equity Attributable to Parent	5,368,205	4,960,382	$ 4,964,089	$ 4,563,316
Long-term debt	1,600,000	2,000,000
Total capitalization	12,792,124	11,997,024
Current liabilities:
Accounts payable	549,710	455,942
Short-term debt	378,400	598,100
Current maturities of long-term debt	417,000	0
Interest	66,113	63,829
Unrealized loss on derivative instruments	218,443	185,788
Total current liabilities	1,982,072	1,566,718
Liabilities, Noncurrent [Abstract]
Unrealized loss on derivative instruments	171,488	38,049
Total capitalization and liabilities	18,960,391	17,732,453
Related Party
Current assets:
Receivables from affiliates	256,671	256,417
Prepaid Expense and Other Assets	16	19
Parent
Assets
Investments in subsidiaries	5,594,854	5,096,133
Other Property And Investments [Abstract]
Goodwill	1,656,513	1,656,513
Current assets:
Cash and Cash Equivalents, at Carrying Value	817	1,596
Income Taxes Receivable, Current	521	96
Total current assets	258,025	258,128
Assets, Noncurrent [Abstract]
Deferred Tax Assets, Net of Valuation Allowance, Noncurrent	196,210	207,192
Other	1,891	2,673
Assets, Noncurrent, Total	198,101	209,865
Total assets	7,707,493	7,220,639
Capitalization, Long-term Debt and Equity [Abstract]
Stockholders' Equity Attributable to Parent	5,368,205	4,960,382
Long-term debt	1,590,795	1,988,609
Total capitalization	6,959,000	6,948,991
Current liabilities:
Accounts payable	195	153
Short-term debt	338,400	261,500
Current maturities of long-term debt	400,000	0
Interest	9,898	9,995
Total current liabilities	748,493	271,648
Liabilities, Noncurrent [Abstract]
Total capitalization and liabilities	$ 7,707,493	$ 7,220,639

SCHEDULE I CONDENSED FINANCIA_4

SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PUGET ENERGY - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Net Cash Provided by (Used in) Operating Activities	$ 822,823	$ 1,053,395	$ 769,618
Investing Activities:
Net Cash Provided by (Used in) Investing Activities	(1,607,843)	(1,452,518)	(1,005,280)
Financing Activities:
Payments of Dividends	(175,861)	(99,760)	(16,230)
Capital contribution	292,800	0	0
Short-term debt	(219,700)	122,500	301,300
Proceeds from Issuance of Long-term Debt	793,892	396,488	448,075
Repayments of Long-term Debt	0	0	(450,000)
Net Cash Provided by (Used in) Financing Activities	711,146	444,913	301,297
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(73,874)	45,790	65,635
Cash, cash equivalents, and restricted cash at end of period	101,836	148,548
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	140,701	214,575	168,785	$ 103,150
Parent Company [Member]
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Net Cash Provided by (Used in) Operating Activities	96,588	64,506	(10,197)
Investing Activities:
Adjustments to Additional Paid in Capital, Other	(292,800)	(100,000)	(50,000)
Payments for (Proceeds from) Loans Receivable from Subsidiary	(590)	(9,753)	(12,176)
Net Cash Provided by (Used in) Investing Activities	(293,390)	(109,753)	(62,176)
Financing Activities:
Payments of Dividends	(175,861)	(99,760)	(16,230)
Capital contribution	292,800	0	0
Short-term debt	76,900	142,900	84,300
Proceeds from Issuance of Long-term Debt	0	0	448,075
Repayments of Long-term Debt	0	0	(450,000)
Issue costs and others	2,184	2,175	1,370
Net Cash Provided by (Used in) Financing Activities	196,023	45,315	67,515
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect	(779)	68	(4,858)
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 817	$ 1,596	$ 1,528	$ 6,386

SCHEDULE I CONDENSED FINANCIA_5

SCHEDULE I CONDENSED FINANCIAL INFORMATION OF PUGET ENERGY Notes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Ownership percentage	100%
Net Income (Loss)	$ 265,255	$ 53,740	$ 414,345
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	290,884	96,053	417,003
Net Cash Provided by (Used in) Operating Activities	822,823	1,053,395	769,618
Net Cash Provided by (Used in) Investing Activities	(1,607,843)	(1,452,518)	(1,005,280)
Business Combination Adjustment, ASC 805	(4,000)	(4,100)	1,000
Parent Company [Member]
Net Income (Loss)	265,255	53,740	414,345
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	290,884	96,053	417,003
Net Cash Provided by (Used in) Operating Activities	96,588	64,506	(10,197)
Net Cash Provided by (Used in) Investing Activities	(293,390)	(109,753)	(62,176)
Subsidiaries [Member]
Net Income (Loss)	346,148	131,059	490,952
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	374,295	175,709	501,049
Net Cash Provided by (Used in) Operating Activities	879,088	1,091,060	817,461
Net Cash Provided by (Used in) Investing Activities	(1,607,075)	(1,451,878)	(1,001,377)
PSE and PLNG
Net Income (Loss)	$ 338,100	$ 114,800	$ 473,800

SCHEDULE II__VALUATION AND QUAL

SCHEDULE II: VALUATION AND QUALIFYING ACCOUNTS AND RESERVES (Details) - SEC Schedule, 12-09, Allowance, Credit Loss [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Beginning Balance	$ 38,211	$ 41,962	$ 34,958
SEC Schedule, 12-09, Valuation Allowances and Reserves, Additions, Charge to Cost and Expense	43,573	34,724	28,316
SEC Schedule, 12-09, Valuation Allowances and Reserves, Deduction	41,348	38,475	21,312
SEC Schedule, 12-09, Valuation Allowances and Reserves, Amount, Ending Balance	$ 40,436	$ 38,211	$ 41,962