Electric utility segment - Condensed Consolidating Statement of Cash Flows (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Cash flows from operating activities
Net cash provided by operating activities	$ 371,617	$ 74,642
Cash flows from investing activities
Capital expenditures	(235,875)	(147,749)
Other	8,160	15,813
Net cash used in investing activities	(282,854)	(497,031)
Cash flows from financing activities
Common stock dividends	(78,893)	(76,602)
Proceeds from issuance of long-term debt	250,000	67,312
Net increase (decrease) in short-term borrowings with original maturities of three months or less	(91,438)	70,019
Other	(1,662)	(318)
Net cash provided by (used in) financing activities	25,698	275,985
Net increase (decrease) in cash, cash equivalents and restricted cash	114,461	(146,404)
Cash, cash equivalents and restricted cash, beginning of period	204,927	311,462
Cash, cash equivalents and restricted cash, end of period	319,388	165,058
Less: Restricted cash	(5,104)	(5,386)	$ (5,050)
Cash and cash equivalents	314,284	159,672	199,877
Hawaiian Electric Consolidated
Cash flows from operating activities
Net cash provided by operating activities	336,145	44,150
Cash flows from investing activities
Capital expenditures	(230,149)	(140,245)
Advances to affiliates	0	0
Other	4,056	6,685
Net cash used in investing activities	(226,093)	(133,560)
Cash flows from financing activities
Common stock dividends	(64,500)	(62,950)
Preferred stock dividends of Hawaiian Electric and subsidiaries	(998)	(998)
Proceeds from issuance of long-term debt	150,000	60,000
Net increase (decrease) in short-term borrowings with original maturities of three months or less	(87,967)	54,987
Payments of obligations under finance leases	(1,339)	0
Other	(843)	(255)
Net cash provided by (used in) financing activities	(5,647)	50,784
Net increase (decrease) in cash, cash equivalents and restricted cash	104,405	(38,626)
Cash, cash equivalents and restricted cash, beginning of period	39,242	55,258
Cash, cash equivalents and restricted cash, end of period	143,647	16,632
Less: Restricted cash	0	(1,129)
Cash and cash equivalents	143,647	15,503	39,242
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaiian Electric
Cash flows from operating activities
Net cash provided by operating activities	274,412	25,367
Cash flows from investing activities
Capital expenditures	(152,823)	(87,892)
Advances to affiliates	0	(2,000)
Other	2,086	4,471
Net cash used in investing activities	(150,737)	(85,421)
Cash flows from financing activities
Common stock dividends	(64,500)	(62,950)
Preferred stock dividends of Hawaiian Electric and subsidiaries	(540)	(540)
Proceeds from issuance of long-term debt	100,000	40,000
Net increase (decrease) in short-term borrowings with original maturities of three months or less	(114,167)	64,987
Payments of obligations under finance leases	(1,241)
Other	(571)	(169)
Net cash provided by (used in) financing activities	(81,019)	41,328
Net increase (decrease) in cash, cash equivalents and restricted cash	42,656	(18,726)
Cash, cash equivalents and restricted cash, beginning of period	27,579	26,433
Cash, cash equivalents and restricted cash, end of period	70,235	7,707
Less: Restricted cash		(1,129)
Cash and cash equivalents	70,235	6,578	27,579
Hawaiian Electric Consolidated | Reportable Legal Entities | Hawaii Electric Light
Cash flows from operating activities
Net cash provided by operating activities	43,352	19,742
Cash flows from investing activities
Capital expenditures	(33,512)	(23,638)
Advances to affiliates	4,500	0
Other	912	834
Net cash used in investing activities	(28,100)	(22,804)
Cash flows from financing activities
Common stock dividends	(8,950)	(8,200)
Preferred stock dividends of Hawaiian Electric and subsidiaries	(267)	(267)
Proceeds from issuance of long-term debt	25,000	10,000
Net increase (decrease) in short-term borrowings with original maturities of three months or less	0	2,000
Payments of obligations under finance leases	(98)
Other	(135)	(43)
Net cash provided by (used in) financing activities	15,550	3,490
Net increase (decrease) in cash, cash equivalents and restricted cash	30,802	428
Cash, cash equivalents and restricted cash, beginning of period	5,092	5,326
Cash, cash equivalents and restricted cash, end of period	35,894	5,754
Less: Restricted cash		0
Cash and cash equivalents	35,894	5,754	5,092
Hawaiian Electric Consolidated | Reportable Legal Entities | Maui Electric
Cash flows from operating activities
Net cash provided by operating activities	34,681	14,841
Cash flows from investing activities
Capital expenditures	(43,814)	(28,715)
Advances to affiliates	21,700	(10,000)
Other	1,058	1,380
Net cash used in investing activities	(21,056)	(37,335)
Cash flows from financing activities
Common stock dividends	(7,350)	(7,600)
Preferred stock dividends of Hawaiian Electric and subsidiaries	(191)	(191)
Proceeds from issuance of long-term debt	25,000	10,000
Net increase (decrease) in short-term borrowings with original maturities of three months or less	0	0
Payments of obligations under finance leases
Other	(137)	(43)
Net cash provided by (used in) financing activities	17,322	2,166
Net increase (decrease) in cash, cash equivalents and restricted cash	30,947	(20,328)
Cash, cash equivalents and restricted cash, beginning of period	6,494	23,422
Cash, cash equivalents and restricted cash, end of period	37,441	3,094
Less: Restricted cash		0
Cash and cash equivalents	37,441	3,094	6,494
Hawaiian Electric Consolidated | Reportable Legal Entities | Other subsidiary
Cash flows from operating activities
Net cash provided by operating activities	0	0
Cash flows from investing activities
Capital expenditures	0	0
Advances to affiliates	0	0
Other	0	0
Net cash used in investing activities	0	0
Cash flows from financing activities
Common stock dividends	0	0
Preferred stock dividends of Hawaiian Electric and subsidiaries	0	0
Proceeds from issuance of long-term debt	0	0
Net increase (decrease) in short-term borrowings with original maturities of three months or less	0	0
Payments of obligations under finance leases
Other	0	0
Net cash provided by (used in) financing activities	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	0	0
Cash, cash equivalents and restricted cash, beginning of period	77	77
Cash, cash equivalents and restricted cash, end of period	77	77
Less: Restricted cash		0
Cash and cash equivalents	77	77	77
Hawaiian Electric Consolidated | Consolidating adjustments
Cash flows from operating activities
Net cash provided by operating activities	(16,300)	(15,800)
Cash flows from investing activities
Capital expenditures	0	0
Advances to affiliates	(26,200)	12,000
Other	0	0
Net cash used in investing activities	(26,200)	12,000
Cash flows from financing activities
Common stock dividends	16,300	15,800
Preferred stock dividends of Hawaiian Electric and subsidiaries	0	0
Proceeds from issuance of long-term debt	0	0
Net increase (decrease) in short-term borrowings with original maturities of three months or less	26,200	(12,000)
Payments of obligations under finance leases
Other	0	0
Net cash provided by (used in) financing activities	42,500	3,800
Net increase (decrease) in cash, cash equivalents and restricted cash	0	0
Cash, cash equivalents and restricted cash, beginning of period	0	0
Cash, cash equivalents and restricted cash, end of period	0	0
Less: Restricted cash		0
Cash and cash equivalents	$ 0	$ 0	$ 0