Condensed Consolidated Statements of Changes in Common Stock Equity (unaudited) - 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 at Dec. 31, 2015	$ 1,927,640	$ 324,766	$ (26,262)	$ 1,728,325	$ 105,388	$ 578,930	$ 1,043,082	$ 925
Beginning Balance (in shares) at Dec. 31, 2015					15,805,000
Increase (decrease) in stockholders' equity
Net income for common stock	32,352	32,352		25,367			25,367
Other comprehensive income, net of taxes	8,800		8,800	1,016				1,016
Common stock dividends	(33,367)	(33,367)		(23,400)			(23,400)
Common stock issuance expenses				(4)		(4)
Ending Balance at Mar. 31, 2016	1,942,179	323,751	(17,462)	1,731,304	$ 105,388	578,926	1,045,049	1,941
Ending Balance (in shares) at Mar. 31, 2016					15,805,000
Beginning Balance at Dec. 31, 2016	$ 2,066,753	438,972	(33,129)	1,799,787	$ 106,818	601,491	1,091,800	(322)
Beginning Balance (in shares) at Dec. 31, 2016	108,583,413				16,020,000
Increase (decrease) in stockholders' equity
Net income for common stock	$ 34,193	34,193		21,465			21,465
Other comprehensive income, net of taxes	985		985	459				459
Common stock dividends	(33,713)	(33,713)		(21,942)			(21,942)
Ending Balance at Mar. 31, 2017	$ 2,065,588	$ 439,452	$ (32,144)	$ 1,799,769	$ 106,818	$ 601,491	$ 1,091,323	$ 137
Ending Balance (in shares) at Mar. 31, 2017	108,745,265				16,020,000