Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income (loss) for common stock	$ 30,747	$ (104,402)	$ 83,503	$ (1,357,764)
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 nil, $13,470, nil and $7,878, respectively	0	36,795	0	21,520
Amortization of unrealized holding losses on held-to-maturity securities, net of taxes of nil, $1,231, nil and $3,565, respectively	0	3,366	0	9,740
Derivatives qualifying as cash flow hedges:
Unrealized interest rate hedging gains (losses) arising during the period, net of taxes of $46, $(291), $(169) and $(24), respectively	131	(838)	(489)	(69)
Reclassification adjustment to net income, net of taxes of $(304), $(18), $(339) and $(52), respectively	(877)	(52)	(977)	(151)
Retirement benefit plans:
Adjustment for amortization of net gains recognized during the period in net periodic benefit cost, net of taxes of $(187), $(431), $(538) and $(740), respectively	(540)	(1,244)	(1,553)	(2,138)
Reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, net of taxes of $192, $462, $527 and $781, respectively	552	1,333	1,519	2,251
Other comprehensive income (loss), net of taxes	(734)	39,360	(1,500)	31,153
Comprehensive income (loss) attributable to Hawaiian Electric Industries, Inc.	$ 30,013	$ (65,042)	$ 82,003	$ (1,326,611)