Condensed Consolidated Statements of Changes in Shareholders' Equity and Common Stock Equity (unaudited) - USD ($) $ in Thousands	Total	Hawaiian Electric Company, Inc. and Subsidiaries	Common stock	Common stock Hawaiian Electric Company, Inc. and Subsidiaries	Premium on capital stock Hawaiian Electric Company, Inc. and Subsidiaries	Retained Earnings	Retained Earnings Hawaiian Electric Company, Inc. and Subsidiaries	Accumulated other comprehensive income (loss)	Accumulated other comprehensive income (loss) Hawaiian Electric Company, Inc. and Subsidiaries
Beginning Balance at Dec. 31, 2018	$ 2,162,280	$ 1,957,641	$ 1,669,267	$ 111,696	$ 681,305	$ 543,623	$ 1,164,541	$ (50,610)	$ 99
Beginning Balance (in shares) at Dec. 31, 2018			108,879,000	16,751,000
Increase (decrease) in stockholders' equity
Net income for common stock	45,688	32,126				45,688	32,126
Other comprehensive income (loss), net of tax (benefits)	9,241	24						9,241	24
Share-based expenses and other, net (in shares)			58,000
Share-based expenses and other, net	1,166		$ 1,166
Common stock dividends	(34,860)	(25,313)				(34,860)	(25,313)
Ending Balance at Mar. 31, 2019	$ 2,183,515	1,964,478	$ 1,670,433	$ 111,696	681,305	554,451	1,171,354	(41,369)	123
Ending Balance (in shares) at Mar. 31, 2019			108,937,000	16,751,000
Increase (decrease) in stockholders' equity
Common stock dividends (in dollars per share)	$ 0.32
Impact of adoption of ASU No. 2016-13	$ (15,372)					(15,372)
Balance, January 1, 2020 after adoption of ASU No. 2016-13	2,264,888		$ 1,678,257			606,670		(20,039)
Beginning Balance at Dec. 31, 2019	$ 2,280,260	2,047,352	$ 1,678,257	$ 113,678	714,824	622,042	1,220,129	(20,039)	(1,279)
Beginning Balance (in shares) at Dec. 31, 2019	108,973,328		108,973,000	17,048,000
Increase (decrease) in stockholders' equity
Net income for common stock	$ 33,420	23,905				33,420	23,905
Other comprehensive income (loss), net of tax (benefits)	18,212	26						18,212	26
Share-based expenses and other, net (in shares)			172,000
Share-based expenses and other, net	(3,996)		$ (3,996)
Common stock dividends	(36,019)	(26,784)				(36,019)	(26,784)
Ending Balance at Mar. 31, 2020	$ 2,276,505	$ 2,044,499	$ 1,674,261	$ 113,678	$ 714,824	$ 604,071	$ 1,217,250	$ (1,827)	$ (1,253)
Ending Balance (in shares) at Mar. 31, 2020	109,145,492		109,145,000	17,048,000
Increase (decrease) in stockholders' equity
Common stock dividends (in dollars per share)	$ 0.33