Electric utility subsidiary - Consolidating financial statements (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Balance			$ 1,727,070	$ 1,593,865
Net income for common stock	41,421	40,588	87,348	74,267
Other comprehensive income (loss), net of taxes	2,900	(8,305)	4,067	(8,366)
Common stock dividends			(62,916)	(61,004)
Balance	1,760,879	1,624,649	1,760,879	1,624,649
Hawaiian Electric Company
Balance			1,593,564	1,472,136
Net income for common stock	34,230	28,693	69,650	53,122
Other comprehensive income (loss), net of taxes	13	17	22	35
Common stock dividends			(44,246)	(40,789)
Common stock issuance expenses			(3)
Balance	1,618,987	1,484,504	1,618,987	1,484,504
HELCO
Balance			274,802	268,908
Net income for common stock	4,846	4,880	10,007	9,300
Other comprehensive income (loss), net of taxes	0	1	0	(1)
Common stock dividends			(5,813)	(7,194)
Common stock issuance expenses			1
Balance	278,995	271,013	278,995	271,013
Maui Electric
Balance			248,771	228,927
Net income for common stock	5,013	3,788	8,769	10,353
Other comprehensive income (loss), net of taxes	0	(1)	0	0
Common stock dividends			(7,175)	(7,008)
Common stock issuance expenses			0
Balance	250,365	232,272	250,365	232,272
Other subsidiaries
Balance			101	104
Net income for common stock	0	(1)	0	(1)
Other comprehensive income (loss), net of taxes	0	0	0	0
Balance	101	103	101	103
Consolidating adjustments
Balance			(523,674)	(497,939)
Net income for common stock	(9,859)	(8,667)	(18,776)	(19,652)
Other comprehensive income (loss), net of taxes	0	0	0	1
Common stock dividends			12,988	14,202
Common stock issuance expenses			1
Balance	(529,461)	(503,388)	(529,461)	(503,388)
HECO Consolidated
Balance			1,593,564	1,472,136
Net income for common stock	34,230	28,693	69,650	53,122
Other comprehensive income (loss), net of taxes	13	17	22	35
Common stock dividends			(44,246)	(40,789)
Common stock issuance expenses			(3)
Balance	$ 1,618,987	$ 1,484,504	$ 1,618,987	$ 1,484,504