Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income for common stock	$ 41,118	$ 62,082	$ 150,449	$ 183,790
Net unrealized gains (losses) on available-for-sale investment securities:
Net unrealized losses on available-for-sale investment securities arising during the period, net of taxes of $(13,918), $(36,230), $(11,860) and $(112,838), respectively	(38,016)	(98,965)	(32,395)	(308,229)
Amortization of unrealized holding losses on held-to-maturity securities, net of taxes of $1,354, nil, $4,050 and nil, respectively	3,699	0	11,065	0
Derivatives qualifying as cash flow hedges:
Unrealized interest rate hedging gains (losses) arising during the period, net of taxes of $(185), $901, $(237) and $2,220, respectively	(535)	2,597	(684)	6,400
Reclassification adjustment to net income, net of taxes of $(17), $19, $(50) and $56, respectively	(47)	53	(143)	161
Retirement benefit plans:
Adjustment for amortization of prior service credit and net losses (gains) recognized during the period in net periodic benefit cost, net of taxes of $(153), $1,943, $(397) and $3,549, respectively	(446)	5,606	(1,160)	10,229
Reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, net of taxes of $163, $(1,839), $458 and $(3,320), respectively	470	(5,303)	1,321	(9,572)
Other comprehensive income (loss), net of taxes	(34,875)	(96,012)	(21,996)	(301,011)
Comprehensive income (loss) attributable to Hawaiian Electric Industries, Inc.	$ 6,243	$ (33,930)	$ 128,453	$ (117,221)