Electric utility segment - Schedule of Consolidating Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Nov. 01, 2024	Dec. 31, 2023	Dec. 31, 2022
Utility property, plant and equipment
Right-of-use assets - finance lease	$ 539,485	$ 448,527
Total property, plant and equipment, net	6,188,372	6,134,318
Current assets
Cash and cash equivalents	501,778	750,535		$ 244,091
Customer accounts receivable, net	491,526	457,171
Regulatory assets	50,039	53,895
Total current assets	1,884,576	2,134,326
Other long-term assets
Operating lease right-of-use-assets	56,604	66,553
Regulatory assets	258,076	227,424
Defined benefit pension and other postretirement benefit plans asset	219,211	107,335
Other	316,040	261,460
Total assets	8,922,879	8,931,416		7,677,372
Capitalization
Total shareholders’ equity	1,605,919	1,479,089		2,344,841	$ 2,202,499
Cumulative preferred stock – not subject to mandatory redemption	0	34,293
Current liabilities
Current portion of long-term debt, net	124,959	109,171
Accounts payable	219,062	203,452
Interest and dividends payable	31,458	27,203
Regulatory liabilities	51,997	26,568
Wildfire tort-related claims	530,000	478,750
Other	410,458	430,824
Total current liabilities	1,427,737	1,324,591
Noncurrent liabilities:
Operating lease liabilities	43,278	56,523
Finance lease liabilities	505,590	426,598
Regulatory liabilities	1,392,147	1,217,515
Wildfire tort-related claims	1,436,250	1,436,250
Defined benefit plans liability	23,656	23,213
Other	203,286	242,957
Total capitalization and liabilities	8,922,879	8,931,416
Hawaiian Electric Company, Inc. and Subsidiaries
Utility property, plant and equipment
Land	52,107	52,019
Plant and equipment	8,719,617	8,421,501
Right-of-use assets - finance lease	539,485	447,101
Less accumulated depreciation	(3,508,592)	(3,326,624)
Construction in progress	382,147	365,709
Utility property, plant and equipment, net	6,184,764	5,959,706
Nonutility property, plant and equipment, less accumulated depreciation	2,705	2,792
Total property, plant and equipment, net	6,187,469	5,962,498
Investment in wholly owned subsidiaries, at equity	0	0
Current assets
Cash and cash equivalents	486,220	184,148		106,077
Advances to affiliates		0
Customer accounts receivable, net	172,894	199,898
Accrued unbilled revenues, net	192,033	178,721
Other accounts receivable, net	76,346	69,637
Fuel oil stock, at average cost	113,582	98,903
Materials and supplies, at average cost	132,803	118,466
Prepayments and other	57,980	151,220
Regulatory assets	50,039	53,895
Total current assets	1,281,897	1,054,888
Other long-term assets
Operating lease right-of-use-assets	55,863	59,281
Regulatory assets	258,076	227,424
Defined benefit pension and other postretirement benefit plans asset	219,477	108,819
Investment in unconsolidated affiliate	287,250	0
Other	240,488	200,694
Total other long-term assets	1,061,154	596,218
Total assets	8,530,520	7,613,604
Capitalization
Total shareholders’ equity	1,583,399	1,156,955		2,409,110	2,344,170
Cumulative preferred stock – not subject to mandatory redemption	0	34,293
Long-term debt, net	2,057,874	1,854,214
Total capitalization	3,641,273	3,045,462
Current liabilities
Current portion of operating lease liabilities	17,565	15,202
Current portion of long-term debt, net	124,959	47,000
Accounts payable	217,203	196,980
Interest and dividends payable	28,024	21,536
Taxes accrued, including revenue taxes	263,179	272,001
Regulatory liabilities	51,997	26,568
Wildfire tort-related claims	482,250	478,750	$ 479,000
Other	119,278	121,011
Total current liabilities	1,304,455	1,227,671
Noncurrent liabilities:
Operating lease liabilities	42,753	49,135
Finance lease liabilities	505,590	425,625
Deferred income taxes	0	0
Regulatory liabilities	1,392,147	1,217,515
Unamortized tax credits	67,918	76,676
Wildfire tort-related claims	1,436,250	1,436,250
Defined benefit plans liability	6,909	6,428
Other	133,225	128,842
Total deferred credits and other liabilities	3,584,792	3,340,471
Total capitalization and liabilities	8,530,520	7,613,604
Hawaiian Electric Company, Inc. and Subsidiaries | Nonrelated Party
Current liabilities
Short-term borrowings	0	48,623
Hawaiian Electric Company, Inc. and Subsidiaries | Affiliated Entity
Current liabilities
Short-term borrowings		0
Consolidating adjustments | Hawaiian Electric Company, Inc. and Subsidiaries
Utility property, plant and equipment
Land	0	0
Plant and equipment	0	0
Right-of-use assets - finance lease	0	0
Less accumulated depreciation	0	0
Construction in progress	0	0
Utility property, plant and equipment, net	0	0
Nonutility property, plant and equipment, less accumulated depreciation	0	0
Total property, plant and equipment, net	0	0
Investment in wholly owned subsidiaries, at equity	(734,296)	(680,414)
Current assets
Cash and cash equivalents	0	0		0
Advances to affiliates		(62,200)
Customer accounts receivable, net	0	0
Accrued unbilled revenues, net	0	0
Other accounts receivable, net	(227,245)	(249,946)
Fuel oil stock, at average cost	0	0
Materials and supplies, at average cost	0	0
Prepayments and other	(2,449)	(6,705)
Regulatory assets	0	0
Total current assets	(229,694)	(318,851)
Other long-term assets
Operating lease right-of-use-assets	0	0
Regulatory assets	0	0
Defined benefit pension and other postretirement benefit plans asset	0	(11,998)
Investment in unconsolidated affiliate	0
Other	(150,914)	(33,626)
Total other long-term assets	(150,914)	(45,624)
Total assets	(1,114,904)	(1,044,889)
Capitalization
Total shareholders’ equity	(734,296)	(680,414)		(722,211)	(701,833)
Cumulative preferred stock – not subject to mandatory redemption		0
Long-term debt, net	(115,000)	0
Total capitalization	(849,296)	(680,414)
Current liabilities
Current portion of operating lease liabilities	0	0
Current portion of long-term debt, net	0	0
Accounts payable	0	0
Interest and dividends payable	(1,112)	(350)
Taxes accrued, including revenue taxes	(2,449)	(6,705)
Regulatory liabilities	0	0
Wildfire tort-related claims	0	0
Other	(226,133)	(249,597)
Total current liabilities	(229,694)	(318,852)
Noncurrent liabilities:
Operating lease liabilities	0	0
Finance lease liabilities	0	0
Deferred income taxes	(35,914)	(33,625)
Regulatory liabilities	0	0
Unamortized tax credits	0	0
Wildfire tort-related claims	0	0
Defined benefit plans liability	0	(11,998)
Other	0	0
Total deferred credits and other liabilities	(35,914)	(45,623)
Total capitalization and liabilities	(1,114,904)	(1,044,889)
Consolidating adjustments | Hawaiian Electric Company, Inc. and Subsidiaries | Nonrelated Party
Current liabilities
Short-term borrowings		0
Consolidating adjustments | Hawaiian Electric Company, Inc. and Subsidiaries | Affiliated Entity
Current liabilities
Short-term borrowings		(62,200)
Hawaiian Electric
Utility property, plant and equipment
Total property, plant and equipment, net	903	1,300
Current assets
Cash and cash equivalents	9,769	564,184		136,510
Total current assets	65,193	592,238
Other long-term assets
Total assets	1,970,127	2,358,877
Capitalization
Total shareholders’ equity	1,605,919	1,479,089
Current liabilities
Current portion of long-term debt, net	0	49,962
Accounts payable	2,156	4,982
Wildfire tort-related claims	47,750	0
Other	65,184	69,295
Total current liabilities	115,582	127,501
Noncurrent liabilities:
Other	2,493	2,575
Total capitalization and liabilities	1,970,127	2,358,877
Hawaiian Electric | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries
Utility property, plant and equipment
Land	42,860	42,860
Plant and equipment	5,667,936	5,502,198
Right-of-use assets - finance lease	411,545	360,270
Less accumulated depreciation	(2,165,110)	(2,029,719)
Construction in progress	283,687	282,150
Utility property, plant and equipment, net	4,240,918	4,157,759
Nonutility property, plant and equipment, less accumulated depreciation	1,146	1,145
Total property, plant and equipment, net	4,242,064	4,158,904
Investment in wholly owned subsidiaries, at equity	734,296	680,414
Current assets
Cash and cash equivalents	396,215	118,367		89,755
Advances to affiliates		62,200
Customer accounts receivable, net	7,278	19,050
Accrued unbilled revenues, net	24,826	12,738
Other accounts receivable, net	196,783	209,752
Fuel oil stock, at average cost	84,938	70,800
Materials and supplies, at average cost	75,754	69,602
Prepayments and other	38,321	110,516
Regulatory assets	32,461	36,520
Total current assets	856,576	709,545
Other long-term assets
Operating lease right-of-use-assets	34,743	29,868
Regulatory assets	177,678	172,257
Defined benefit pension and other postretirement benefit plans asset	134,785	66,292
Investment in unconsolidated affiliate	287,250
Other	344,052	194,006
Total other long-term assets	978,508	462,423
Total assets	6,811,444	6,011,286
Capitalization
Total shareholders’ equity	1,583,399	1,156,955		2,409,110	2,344,170
Cumulative preferred stock – not subject to mandatory redemption		22,293
Long-term debt, net	1,619,482	1,353,173
Total capitalization	3,202,881	2,532,421
Current liabilities
Current portion of operating lease liabilities	5,716	4,430
Current portion of long-term debt, net	61,980	40,000
Accounts payable	150,843	137,837
Interest and dividends payable	22,582	15,994
Taxes accrued, including revenue taxes	184,339	197,768
Regulatory liabilities	23,127	11,701
Wildfire tort-related claims	386,500	383,000
Other	93,475	103,415
Total current liabilities	928,562	942,768
Noncurrent liabilities:
Operating lease liabilities	32,974	29,830
Finance lease liabilities	382,227	341,364
Deferred income taxes	0	0
Regulatory liabilities	980,131	864,259
Unamortized tax credits	47,973	54,950
Wildfire tort-related claims	1,149,000	1,149,000
Defined benefit plans liability	6,788	18,301
Other	80,908	78,393
Total deferred credits and other liabilities	2,680,001	2,536,097
Total capitalization and liabilities	6,811,444	6,011,286
Hawaiian Electric | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Nonrelated Party
Current liabilities
Short-term borrowings		48,623
Hawaiian Electric | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Affiliated Entity
Current liabilities
Short-term borrowings		0
Hawaii Electric Light | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries
Utility property, plant and equipment
Land	5,644	5,645
Plant and equipment	1,564,628	1,501,947
Right-of-use assets - finance lease	77,183	36,074
Less accumulated depreciation	(716,715)	(691,161)
Construction in progress	34,021	31,341
Utility property, plant and equipment, net	964,761	883,846
Nonutility property, plant and equipment, less accumulated depreciation	115	115
Total property, plant and equipment, net	964,876	883,961
Investment in wholly owned subsidiaries, at equity	0	0
Current assets
Cash and cash equivalents	56,563	31,534		10,658
Advances to affiliates		0
Customer accounts receivable, net	2,987	7,245
Accrued unbilled revenues, net	7,462	4,046
Other accounts receivable, net	55,970	58,366
Fuel oil stock, at average cost	11,997	13,764
Materials and supplies, at average cost	19,184	15,506
Prepayments and other	9,657	16,662
Regulatory assets	10,279	8,211
Total current assets	174,099	155,334
Other long-term assets
Operating lease right-of-use-assets	16,219	22,672
Regulatory assets	28,245	18,875
Defined benefit pension and other postretirement benefit plans asset	45,794	30,397
Investment in unconsolidated affiliate	0
Other	18,374	18,612
Total other long-term assets	108,632	90,556
Total assets	1,247,607	1,129,851
Capitalization
Total shareholders’ equity	276,332	243,964		359,790	344,720
Cumulative preferred stock – not subject to mandatory redemption		7,000
Long-term debt, net	261,614	244,466
Total capitalization	537,946	495,430
Current liabilities
Current portion of operating lease liabilities	8,570	7,802
Current portion of long-term debt, net	7,997	5,000
Accounts payable	34,072	27,077
Interest and dividends payable	3,440	3,191
Taxes accrued, including revenue taxes	40,720	42,692
Regulatory liabilities	12,410	10,039
Wildfire tort-related claims	47,875	47,875
Other	37,759	35,492
Total current liabilities	192,843	179,168
Noncurrent liabilities:
Operating lease liabilities	7,932	15,230
Finance lease liabilities	74,087	34,370
Deferred income taxes	12,089	5,368
Regulatory liabilities	248,885	222,834
Unamortized tax credits	9,794	10,757
Wildfire tort-related claims	143,625	143,625
Defined benefit plans liability	121	125
Other	20,285	22,944
Total deferred credits and other liabilities	516,818	455,253
Total capitalization and liabilities	1,247,607	1,129,851
Hawaii Electric Light | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Nonrelated Party
Current liabilities
Short-term borrowings		0
Hawaii Electric Light | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Affiliated Entity
Current liabilities
Short-term borrowings		0
Maui Electric | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries
Utility property, plant and equipment
Land	3,603	3,514
Plant and equipment	1,487,053	1,417,356
Right-of-use assets - finance lease	50,757	50,757
Less accumulated depreciation	(626,767)	(605,744)
Construction in progress	64,439	52,218
Utility property, plant and equipment, net	979,085	918,101
Nonutility property, plant and equipment, less accumulated depreciation	1,444	1,532
Total property, plant and equipment, net	980,529	919,633
Investment in wholly owned subsidiaries, at equity	0	0
Current assets
Cash and cash equivalents	8,572	16,456		5,587
Advances to affiliates		0
Customer accounts receivable, net	3,942	8,941
Accrued unbilled revenues, net	600	1,890
Other accounts receivable, net	50,838	51,465
Fuel oil stock, at average cost	16,647	14,339
Materials and supplies, at average cost	37,865	33,358
Prepayments and other	12,451	30,747
Regulatory assets	7,299	9,164
Total current assets	138,214	166,360
Other long-term assets
Operating lease right-of-use-assets	4,901	6,741
Regulatory assets	52,153	36,292
Defined benefit pension and other postretirement benefit plans asset	38,898	24,128
Investment in unconsolidated affiliate	0
Other	28,976	21,702
Total other long-term assets	124,928	88,863
Total assets	1,243,671	1,174,856
Capitalization
Total shareholders’ equity	298,459	282,876		362,344	357,036
Cumulative preferred stock – not subject to mandatory redemption		5,000
Long-term debt, net	291,778	256,575
Total capitalization	590,237	544,451
Current liabilities
Current portion of operating lease liabilities	3,279	2,970
Current portion of long-term debt, net	54,982	2,000
Accounts payable	32,288	32,066
Interest and dividends payable	3,114	2,701
Taxes accrued, including revenue taxes	37,374	37,108
Regulatory liabilities	16,460	4,828
Wildfire tort-related claims	47,875	47,875
Other	34,175	43,913
Total current liabilities	229,547	235,661
Noncurrent liabilities:
Operating lease liabilities	1,847	4,075
Finance lease liabilities	49,276	49,891
Deferred income taxes	23,825	28,257
Regulatory liabilities	163,131	130,422
Unamortized tax credits	10,151	10,969
Wildfire tort-related claims	143,625	143,625
Defined benefit plans liability	0	0
Other	32,032	27,505
Total deferred credits and other liabilities	423,887	394,744
Total capitalization and liabilities	1,243,671	1,174,856
Maui Electric | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Nonrelated Party
Current liabilities
Short-term borrowings		0
Maui Electric | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Affiliated Entity
Current liabilities
Short-term borrowings		62,200
Other subsidiaries | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries
Utility property, plant and equipment
Land	0	0
Plant and equipment	0	0
Right-of-use assets - finance lease	0	0
Less accumulated depreciation	0	0
Construction in progress	0	0
Utility property, plant and equipment, net	0	0
Nonutility property, plant and equipment, less accumulated depreciation	0	0
Total property, plant and equipment, net	0	0
Investment in wholly owned subsidiaries, at equity	0	0
Current assets
Cash and cash equivalents	24,870	17,791		77
Advances to affiliates		0
Customer accounts receivable, net	158,687	164,662
Accrued unbilled revenues, net	159,145	160,047
Other accounts receivable, net	0	0
Fuel oil stock, at average cost	0	0
Materials and supplies, at average cost	0	0
Prepayments and other	0	0
Regulatory assets	0	0
Total current assets	342,702	342,500
Other long-term assets
Operating lease right-of-use-assets	0	0
Regulatory assets	0	0
Defined benefit pension and other postretirement benefit plans asset	0	0
Investment in unconsolidated affiliate	0
Other	0	0
Total other long-term assets	0	0
Total assets	342,702	342,500
Capitalization
Total shareholders’ equity	159,505	153,574		$ 77	$ 77
Cumulative preferred stock – not subject to mandatory redemption		0
Long-term debt, net	0	0
Total capitalization	159,505	153,574
Current liabilities
Current portion of operating lease liabilities	0	0
Current portion of long-term debt, net	0	0
Accounts payable	0	0
Interest and dividends payable	0	0
Taxes accrued, including revenue taxes	3,195	1,138
Regulatory liabilities	0	0
Wildfire tort-related claims	0	0
Other	180,002	187,788
Total current liabilities	183,197	188,926
Noncurrent liabilities:
Operating lease liabilities	0	0
Finance lease liabilities	0	0
Deferred income taxes	0	0
Regulatory liabilities	0	0
Unamortized tax credits	0	0
Wildfire tort-related claims	0	0
Defined benefit plans liability	0	0
Other	0	0
Total deferred credits and other liabilities	0	0
Total capitalization and liabilities	$ 342,702	342,500
Other subsidiaries | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Nonrelated Party
Current liabilities
Short-term borrowings		0
Other subsidiaries | Reportable Legal Entities | Hawaiian Electric Company, Inc. and Subsidiaries | Affiliated Entity
Current liabilities
Short-term borrowings		$ 0