Electric utility segment - Condensed Consolidating Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021
Utility property, plant and equipment
Total property, plant and equipment, net	$ 5,868,408		$ 5,687,003
Current assets
Cash and cash equivalents	314,284		199,877	$ 159,672
Other long-term assets
Operating lease right-of-use assets	105,030		115,684
Total assets	16,519,309		16,284,244
Capitalization
Common stock equity	2,249,377	$ 2,237,955	2,202,499	2,233,504	$ 2,303,642	$ 2,390,884
Preferred stock of subsidiaries - not subject to mandatory redemption	34,293		34,293
Current liabilities
Short-term borrowings	46,212		172,568
Interest and dividends payable	33,294		21,333
Deferred credits and other liabilities
Deferred income taxes	272,988		262,462
Total liabilities and shareholders’ equity	16,519,309		16,284,244
Hawaiian Electric Consolidated
Utility property, plant and equipment
Land	52,098		52,060
Plant and equipment	8,122,766		7,979,510
Financing lease right-of-use assets	124,372		48,371
Less accumulated depreciation	(3,178,967)		(3,086,499)
Construction in progress	338,052		275,353
Utility property, plant and equipment, net	5,458,321		5,268,795
Nonutility property, plant and equipment, less accumulated depreciation	6,944		6,945
Total property, plant and equipment, net	5,465,265		5,275,740
Investment in wholly owned subsidiaries, at equity	0		0
Current assets
Cash and cash equivalents	143,647		39,242	15,503
Advances to affiliates			0
Customer accounts receivable, net	209,194		288,338
Accrued unbilled revenues, net	154,355		183,280
Other accounts receivable, net	17,725		13,567
Fuel oil stock, at average cost	143,800		191,530
Materials and supplies, at average cost	91,155		79,568
Prepayments and other	41,880		33,482
Regulatory assets	77,237		52,273
Total current assets	878,993		881,280
Other long-term assets
Operating lease right-of-use assets	80,505		89,318
Regulatory assets	175,550		190,240
Other	161,280		160,889
Total other long-term assets	417,335		440,447
Total assets	6,761,593		6,597,467
Capitalization
Common stock equity	2,371,889	$ 2,358,884	2,344,170	2,289,595	$ 2,276,884	2,261,899
Preferred stock of subsidiaries - not subject to mandatory redemption	34,293		34,293
Long-term debt, net	1,734,530		1,584,854
Total capitalization	4,140,712		3,963,317
Current liabilities
Current portion of operating lease liabilities	17,709		19,095
Current portion of long-term debt	99,985		99,962
Accounts payable	210,632		202,492
Interest and dividends payable	21,367		17,176
Taxes accrued, including revenue taxes	252,937		289,902
Regulatory liabilities	25,938		31,475
Other	90,295		85,596
Total current liabilities	718,863		833,665
Deferred credits and other liabilities
Operating lease liabilities	70,465		78,715
Finance lease liabilities	119,006		46,048
Deferred income taxes	385,350		384,430
Regulatory liabilities	1,061,418		1,024,175
Unamortized tax credits	91,590		95,300
Defined benefit pension liability	49,016		49,748
Other	125,173		122,069
Total deferred credits and other liabilities	1,902,018		1,800,485
Total liabilities and shareholders’ equity	6,761,593		6,597,467
Hawaiian Electric Consolidated | Nonrelated Party
Current liabilities
Short-term borrowings	0		87,967
Hawaiian Electric Consolidated | Affiliated Entity
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaiian Electric
Utility property, plant and equipment
Land	42,859		42,860
Plant and equipment	5,370,111		5,260,685
Financing lease right-of-use assets	88,297		48,371
Less accumulated depreciation	(1,921,855)		(1,855,150)
Construction in progress	256,266		215,560
Utility property, plant and equipment, net	3,835,678		3,712,326
Nonutility property, plant and equipment, less accumulated depreciation	5,297		5,298
Total property, plant and equipment, net	3,840,975		3,717,624
Investment in wholly owned subsidiaries, at equity	708,465		701,833
Current assets
Cash and cash equivalents	70,235		27,579	6,578
Advances to affiliates			0
Customer accounts receivable, net	147,065		216,802
Accrued unbilled revenues, net	113,069		136,508
Other accounts receivable, net	26,535		23,746
Fuel oil stock, at average cost	106,515		153,342
Materials and supplies, at average cost	53,681		48,130
Prepayments and other	32,621		24,040
Regulatory assets	70,932		46,504
Total current assets	620,653		676,651
Other long-term assets
Operating lease right-of-use assets	38,675		42,752
Regulatory assets	146,918		154,040
Other	114,318		115,028
Total other long-term assets	299,911		311,820
Total assets	5,470,004		5,407,928
Capitalization
Common stock equity	2,371,889		2,344,170	2,289,595		2,261,899
Preferred stock of subsidiaries - not subject to mandatory redemption	22,293		22,293
Long-term debt, net	1,226,714		1,126,915
Total capitalization	3,620,896		3,493,378
Current liabilities
Current portion of operating lease liabilities	8,128		9,775
Current portion of long-term debt	49,992		49,981
Accounts payable	158,400		143,253
Interest and dividends payable	15,126		12,398
Taxes accrued, including revenue taxes	180,089		207,798
Regulatory liabilities	9,325		13,145
Other	66,765		64,659
Total current liabilities	487,825		615,176
Deferred credits and other liabilities
Operating lease liabilities	37,657		41,049
Finance lease liabilities	83,642		46,048
Deferred income taxes	272,556		271,234
Regulatory liabilities	758,970		729,683
Unamortized tax credits	66,632		69,614
Defined benefit pension liability	65,923		65,907
Other	75,903		75,839
Total deferred credits and other liabilities	1,361,283		1,299,374
Total liabilities and shareholders’ equity	5,470,004		5,407,928
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaiian Electric | Nonrelated Party
Current liabilities
Short-term borrowings			87,967
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaiian Electric | Affiliated Entity
Current liabilities
Short-term borrowings			26,200
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaii Electric Light
Utility property, plant and equipment
Land	5,645		5,606
Plant and equipment	1,436,118		1,425,442
Financing lease right-of-use assets	36,075		0
Less accumulated depreciation	(657,127)		(644,457)
Construction in progress	33,118		23,989
Utility property, plant and equipment, net	853,829		810,580
Nonutility property, plant and equipment, less accumulated depreciation	115		115
Total property, plant and equipment, net	853,944		810,695
Investment in wholly owned subsidiaries, at equity	0		0
Current assets
Cash and cash equivalents	35,894		5,092	5,754
Advances to affiliates			4,500
Customer accounts receivable, net	32,293		39,339
Accrued unbilled revenues, net	20,474		23,839
Other accounts receivable, net	5,602		5,519
Fuel oil stock, at average cost	17,069		16,964
Materials and supplies, at average cost	12,304		9,783
Prepayments and other	5,082		6,346
Regulatory assets	2,789		2,435
Total current assets	131,507		113,817
Other long-term assets
Operating lease right-of-use assets	30,903		34,283
Regulatory assets	16,686		21,816
Other	33,129		32,654
Total other long-term assets	80,718		88,753
Total assets	1,066,169		1,013,265
Capitalization
Common stock equity	349,227		344,720	337,737		332,900
Preferred stock of subsidiaries - not subject to mandatory redemption	7,000		7,000
Long-term debt, net	249,370		224,439
Total capitalization	605,597		576,159
Current liabilities
Current portion of operating lease liabilities	6,861		6,690
Current portion of long-term debt	19,997		19,992
Accounts payable	23,919		32,113
Interest and dividends payable	3,271		2,576
Taxes accrued, including revenue taxes	37,077		42,436
Regulatory liabilities	7,599		8,553
Other	22,001		20,856
Total current liabilities	120,725		133,216
Deferred credits and other liabilities
Operating lease liabilities	24,343		27,817
Finance lease liabilities	35,364		0
Deferred income taxes	50,433		50,615
Regulatory liabilities	196,235		194,222
Unamortized tax credits	12,657		13,150
Defined benefit pension liability	0		129
Other	20,815		17,957
Total deferred credits and other liabilities	339,847		303,890
Total liabilities and shareholders’ equity	1,066,169		1,013,265
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaii Electric Light | Nonrelated Party
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaii Electric Light | Affiliated Entity
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Reportable Legal Entities | Maui Electric
Utility property, plant and equipment
Land	3,594		3,594
Plant and equipment	1,316,537		1,293,383
Financing lease right-of-use assets	0		0
Less accumulated depreciation	(599,985)		(586,892)
Construction in progress	48,668		35,804
Utility property, plant and equipment, net	768,814		745,889
Nonutility property, plant and equipment, less accumulated depreciation	1,532		1,532
Total property, plant and equipment, net	770,346		747,421
Investment in wholly owned subsidiaries, at equity	0		0
Current assets
Cash and cash equivalents	37,441		6,494	3,094
Advances to affiliates			21,700
Customer accounts receivable, net	29,836		32,197
Accrued unbilled revenues, net	20,812		22,933
Other accounts receivable, net	6,143		6,686
Fuel oil stock, at average cost	20,216		21,224
Materials and supplies, at average cost	25,170		21,655
Prepayments and other	4,475		4,137
Regulatory assets	3,516		3,334
Total current assets	147,609		140,360
Other long-term assets
Operating lease right-of-use assets	10,927		12,283
Regulatory assets	11,946		14,384
Other	30,740		29,495
Total other long-term assets	53,613		56,162
Total assets	971,568		943,943
Capitalization
Common stock equity	359,161		357,036	348,524		343,260
Preferred stock of subsidiaries - not subject to mandatory redemption	5,000		5,000
Long-term debt, net	258,446		233,500
Total capitalization	622,607		595,536
Current liabilities
Current portion of operating lease liabilities	2,720		2,630
Current portion of long-term debt	29,996		29,989
Accounts payable	28,313		27,126
Interest and dividends payable	2,970		2,282
Taxes accrued, including revenue taxes	36,069		40,709
Regulatory liabilities	9,014		9,777
Other	22,084		22,385
Total current liabilities	131,166		134,898
Deferred credits and other liabilities
Operating lease liabilities	8,465		9,849
Finance lease liabilities	0		0
Deferred income taxes	62,361		62,581
Regulatory liabilities	106,213		100,270
Unamortized tax credits	12,301		12,536
Defined benefit pension liability	0		0
Other	28,455		28,273
Total deferred credits and other liabilities	217,795		213,509
Total liabilities and shareholders’ equity	971,568		943,943
Hawaiian Electric Consolidated | Reportable Legal Entities | Maui Electric | Nonrelated Party
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Reportable Legal Entities | Maui Electric | Affiliated Entity
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Reportable Legal Entities | Other subsidiary
Utility property, plant and equipment
Land	0		0
Plant and equipment	0		0
Financing lease right-of-use assets	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	77		77	77
Advances to affiliates			0
Customer accounts receivable, net	0		0
Accrued unbilled revenues, net	0		0
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	77		77
Other long-term assets
Operating lease right-of-use assets	0		0
Regulatory assets	0		0
Other	0		0
Total other long-term assets	0		0
Total assets	77		77
Capitalization
Common stock equity	77		77	77		77
Preferred stock of subsidiaries - not subject to mandatory redemption	0		0
Long-term debt, net	0		0
Total capitalization	77		77
Current liabilities
Current portion of operating lease liabilities	0		0
Current portion of long-term debt	0		0
Accounts payable	0		0
Interest and dividends payable	0		0
Taxes accrued, including revenue taxes	0		0
Regulatory liabilities	0		0
Other	0		0
Total current liabilities	0		0
Deferred credits and other 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
Defined benefit pension liability	0		0
Other	0		0
Total deferred credits and other liabilities	0		0
Total liabilities and shareholders’ equity	77		77
Hawaiian Electric Consolidated | Reportable Legal Entities | Other subsidiary | Nonrelated Party
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Reportable Legal Entities | Other subsidiary | Affiliated Entity
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Consolidating adjustments
Utility property, plant and equipment
Land	0		0
Plant and equipment	0		0
Financing lease right-of-use assets	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	(708,465)		(701,833)
Current assets
Cash and cash equivalents	0		0	0
Advances to affiliates			(26,200)
Customer accounts receivable, net	0		0
Accrued unbilled revenues, net	0		0
Other accounts receivable, net	(20,555)		(22,384)
Fuel oil stock, at average cost	0		0
Materials and supplies, at average cost	0		0
Prepayments and other	(298)		(1,041)
Regulatory assets	0		0
Total current assets	(20,853)		(49,625)
Other long-term assets
Operating lease right-of-use assets	0		0
Regulatory assets	0		0
Other	(16,907)		(16,288)
Total other long-term assets	(16,907)		(16,288)
Total assets	(746,225)		(767,746)
Capitalization
Common stock equity	(708,465)		(701,833)	$ (686,338)		$ (676,237)
Preferred stock of subsidiaries - not subject to mandatory redemption	0		0
Long-term debt, net	0		0
Total capitalization	(708,465)		(701,833)
Current liabilities
Current portion of operating lease liabilities	0		0
Current portion of long-term debt	0		0
Accounts payable	0		0
Interest and dividends payable	0		(80)
Taxes accrued, including revenue taxes	(298)		(1,041)
Regulatory liabilities	0		0
Other	(20,555)		(22,304)
Total current liabilities	(20,853)		(49,625)
Deferred credits and other 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
Defined benefit pension liability	(16,907)		(16,288)
Other	0		0
Total deferred credits and other liabilities	(16,907)		(16,288)
Total liabilities and shareholders’ equity	$ (746,225)		(767,746)
Hawaiian Electric Consolidated | Consolidating adjustments | Nonrelated Party
Current liabilities
Short-term borrowings			0
Hawaiian Electric Consolidated | Consolidating adjustments | Affiliated Entity
Current liabilities
Short-term borrowings			$ (26,200)