Consolidated Statements of Changes in Common Stock Equity - HECO - USD ($) $ in Thousands	Total	Retained earnings	Accumulated other comprehensive income (loss)	Hawaiian Electric Company, Inc. and Subsidiaries	Hawaiian Electric Company, Inc. and Subsidiaries Common stock	Hawaiian Electric Company, Inc. and Subsidiaries Premium on capital stock	Hawaiian Electric Company, Inc. and Subsidiaries Retained earnings	Hawaiian Electric Company, Inc. and Subsidiaries Accumulated other comprehensive income (loss)
Beginning balance (in shares) at Dec. 31, 2018					16,751,000
Beginning balance at Dec. 31, 2018	$ 2,162,280	$ 543,623	$ (50,610)	$ 1,957,641	$ 111,696	$ 681,305	$ 1,164,541	$ 99
Increase (decrease) in stockholders' equity
Net income for common stock	217,882	217,882		156,840			156,840
Other comprehensive income (loss), net of taxes (benefits)	30,571		30,571	(1,378)				(1,378)
Issuance of common stock, net of expenses (in shares)					297,000
Issuance of common stock, net of expenses	3,092			35,501	$ 1,982	33,519
Common stock dividends	(139,463)	(139,463)		(101,252)			(101,252)
Ending balance (in shares) at Dec. 31, 2019					17,048,000
Ending balance at Dec. 31, 2019	2,280,260	622,042	(20,039)	2,047,352	$ 113,678	714,824	1,220,129	(1,279)
Increase (decrease) in stockholders' equity
Net income for common stock	197,824	197,824		169,340			169,340
Other comprehensive income (loss), net of taxes (benefits)	18,775		18,775	(1,640)				(1,640)
Issuance of common stock, net of expenses (in shares)					276,000
Issuance of common stock, net of expenses	3,973			34,000	$ 1,837	32,163
Common stock dividends	$ (144,096)	(144,096)		(107,134)			(107,134)
Ending balance (in shares) at Dec. 31, 2020	109,181,124				17,324,000
Ending balance at Dec. 31, 2020	$ 2,337,502	660,398	(1,264)	2,141,918	$ 115,515	746,987	1,282,335	(2,919)
Increase (decrease) in stockholders' equity
Net income for common stock	246,166	246,166		177,642			177,642
Other comprehensive income (loss), net of taxes (benefits)	(51,269)		(51,269)	(361)				(361)
Issuance of common stock, net of expenses (in shares)					429,000
Issuance of common stock, net of expenses	5,027			54,400	$ 2,861	51,539
Common stock dividends	$ (148,643)	(148,643)		(111,700)			(111,700)
Ending balance (in shares) at Dec. 31, 2021	109,311,785				17,753,000
Ending balance at Dec. 31, 2021	$ 2,390,884	$ 757,921	$ (52,533)	$ 2,261,899	$ 118,376	$ 798,526	$ 1,348,277	$ (3,280)