Consolidated Statements of Changes in Common Stock Equity (unaudited) - HECO - USD ($) $ in Thousands	Total	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	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, 2013	$ 1,726,406	$ 1,593,564	$ 102,880	$ 541,452	$ 255,030	$ 948,624	$ (16,750)	$ 608
Balance (in shares) at Dec. 31, 2013			15,429,000
Increase (decrease) in stockholders' equity
Net income for common stock	134,876	108,529			134,876	108,529
Other comprehensive income, net of taxes	2,756	32					2,756	32
Common stock dividends	(94,711)	(66,369)			(94,711)	(66,369)
Common stock issuance expenses		(5)		(5)
Ending Balance at Sep. 30, 2014	1,800,457	1,635,751	$ 102,880	541,447	295,195	990,784	(13,994)	640
Balance (in shares) at Sep. 30, 2014			15,429,000
Beginning Balance at Dec. 31, 2014	$ 1,790,573	1,682,144	$ 105,388	578,938	296,654	997,773	(27,378)	45
Balance (in shares) at Dec. 31, 2014	102,565,266		15,805,000
Increase (decrease) in stockholders' equity
Net income for common stock	$ 117,557	102,721			117,557	102,721
Other comprehensive income, net of taxes	5,361	11					5,361	11
Common stock dividends	(98,452)	(67,804)			(98,452)	(67,804)
Common stock issuance expenses		(8)		(8)
Ending Balance at Sep. 30, 2015	$ 1,921,001	$ 1,717,064	$ 105,388	$ 578,930	$ 315,759	$ 1,032,690	$ (22,017)	$ 56
Balance (in shares) at Sep. 30, 2015	107,458,641		15,805,000