Income taxes - Components of Income Taxes Attributable to Net Income for Common Stock (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Federal
Current	$ 77,595	$ 51,455	$ 23,207
Deferred	(37,410)	(11,689)	(4,215)
Deferred tax credits, net	4,031	4,611	10,979
Federal taxes	44,216	44,377	29,971
State
Current	11,981	12,119	8,430
Deferred	4,914	6,290	2,509
Deferred tax credits, net	56	21	0
State taxes	16,951	18,430	10,939
Total	61,167	62,807	40,910
Hawaiian Electric Company, Inc. and Subsidiaries
Federal
Current	75,118	42,794	31,950
Deferred	(39,646)	(12,109)	(5,408)
Deferred tax credits, net	137	302	1,549
Federal taxes	35,609	30,987	28,091
State
Current	15,780	4,861	3,768
Deferred	(1,769)	8,279	8,559
Deferred tax credits, net	56	21	0
State taxes	14,067	13,161	12,327
Total	$ 49,676	$ 44,148	$ 40,418