Consolidated Statements of Comprehensive Income - HECO - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net income for common stock	$ 42,320	$ 50,673	$ 35,018	$ 31,866	$ 33,253	$ 47,808	$ 41,281	$ 45,787	$ 159,877	$ 168,129	$ 161,709
Retirement benefit plans:
Net gains (losses) arising during the period, net of (taxes) benefits of ($59), $6,164 and ($10,450) for 2015, 2014 and 2013, respectively									5,889	(234,166)	223,177
Less: amortization of transition obligation, prior service credit and net losses recognized during the period in net periodic benefit cost, net of tax benefits of $1,011, $561 and $1,187 for 2015, 2014 and 2013, respectively									22,465	11,344	23,280
Less: reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, net of (taxes) benefits of $16,011, ($132,373) and $141,777 for 2015, 2014 and 2013, respectively									(25,139)	207,833	(222,595)
Other comprehensive income (loss), net of taxes									1,116	(10,628)	9,673
Comprehensive income attributable to Hawaiian Electric Company, Inc.									160,993	157,501	171,382
Hawaiian Electric Company, Inc. and Subsidiaries
Net income for common stock	$ 32,993	$ 43,006	$ 32,841	$ 26,874	$ 29,112	$ 38,879	$ 34,230	$ 35,420	135,714	137,641	122,929
Retirement benefit plans:
Net gains (losses) arising during the period, net of (taxes) benefits of ($59), $6,164 and ($10,450) for 2015, 2014 and 2013, respectively									5,638	(218,608)	203,479
Less: amortization of transition obligation, prior service credit and net losses recognized during the period in net periodic benefit cost, net of tax benefits of $1,011, $561 and $1,187 for 2015, 2014 and 2013, respectively									20,381	10,212	20,694
Less: reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, net of (taxes) benefits of $16,011, ($132,373) and $141,777 for 2015, 2014 and 2013, respectively									(25,139)	207,833	(222,595)
Other comprehensive income (loss), net of taxes									880	(563)	1,578
Comprehensive income attributable to Hawaiian Electric Company, Inc.									$ 136,594	$ 137,078	$ 124,507