Electric utility segment - Condensed Consolidating Statement of Changes in Common Stock Equity (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Increase (decrease) in stockholders' equity
Beginning balance	$ 2,344,841	$ 2,202,499
Net income for common stock	42,122	54,721
Other comprehensive loss, net of taxes	(9,801)	20,488
Common stock dividends		(39,446)
Ending balance	2,377,380	2,237,955
Hawaiian Electric Consolidated
Increase (decrease) in stockholders' equity
Beginning balance	2,409,110	2,344,170
Net income for common stock	39,221	47,009
Other comprehensive loss, net of taxes	(49)	(45)
Common stock dividends	(13,000)	(32,250)
Ending balance	2,435,282	2,358,884
Consolidating adjustments | Hawaiian Electric Consolidated
Increase (decrease) in stockholders' equity
Beginning balance	(722,211)	(701,833)
Net income for common stock	(6,024)	(11,541)
Other comprehensive loss, net of taxes	13	12
Common stock dividends		8,150
Ending balance	(728,222)	(705,212)
Hawaiian Electric | Reportable Legal Entities | Hawaiian Electric Consolidated
Increase (decrease) in stockholders' equity
Beginning balance	2,409,110	2,344,170
Net income for common stock	39,221	47,009
Other comprehensive loss, net of taxes	(49)	(45)
Common stock dividends	(13,000)	(32,250)
Ending balance	2,435,282	2,358,884
Hawaii Electric Light | Reportable Legal Entities | Hawaiian Electric Consolidated
Increase (decrease) in stockholders' equity
Beginning balance	359,790	344,720
Net income for common stock	4,390	6,390
Other comprehensive loss, net of taxes	(3)	(6)
Common stock dividends		(4,475)
Ending balance	364,177	346,629
Maui Electric | Reportable Legal Entities | Hawaiian Electric Consolidated
Increase (decrease) in stockholders' equity
Beginning balance	362,344	357,036
Net income for common stock	1,634	5,151
Other comprehensive loss, net of taxes	(10)	(6)
Common stock dividends		(3,675)
Ending balance	363,968	358,506
Other subsidiaries | Reportable Legal Entities | Hawaiian Electric Consolidated
Increase (decrease) in stockholders' equity
Beginning balance	77	77
Net income for common stock	0	0
Other comprehensive loss, net of taxes	0	0
Ending balance	$ 77	$ 77