Income taxes Components of Income Taxes Attributable to Net Income for Common Stock (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Federal
Federal current taxes	$ (10,970)	$ (1,520)	$ (15,411)
Federal deferred taxes	91,159	73,680	82,138
Deferred tax credits, net	0	224	187
Federal taxes	80,189	72,384	66,914
State
Current	(7,339)	(1,555)	(4,654)
Deferred	12,756	6,719	8,710
Deferred tax credits, net	6,106	6,793	5,889
State taxes	11,523	11,957	9,945
Federal and state taxes	91,712	84,341	76,859
Hawaiian Electric Company, Inc. and Subsidiaries
Federal
Federal current taxes	1,108	1,313	(26,965)
Federal deferred taxes	68,775	58,024	79,437
Deferred tax credits, net	0	224	186
Federal taxes	69,883	59,561	52,658
State
Current	(9,436)	(3,720)	(4,940)
Deferred	14,172	6,483	7,441
Deferred tax credits, net	6,106	6,793	5,889
State taxes	10,842	9,556	8,390
Federal and state taxes	$ 80,725	$ 69,117	$ 61,048