Condensed Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net unrealized gains (losses) on securities arising during the period, taxes (benefits)	$ 1,334	$ 1,925	$ 1,482	$ 6,830
Less: reclassification adjustment to net income - realized gains on available-for-sale investment securities	0	238	0	238
Effective portion of foreign currency hedge net unrealized gains (losses) arising during the period, net of (taxes) benefits of nil, $475, nil and ($163), respectively	0	(475)	0	163
Less: reclassification adjustment to net income, taxes	0	0	(289)	(35)
Less: amortization of prior service credit and net losses recognized during the period in net periodic benefit cost, tax benefits	(2,508)	(2,362)	(5,010)	(4,619)
Less: reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, taxes	2,281	2,166	4,582	4,218
Hawaiian Electric Company, Inc. and Subsidiaries
Effective portion of foreign currency hedge net unrealized gains (losses) arising during the period, net of (taxes) benefits of nil, $475, nil and ($163), respectively	0	(475)	0	163
Less: reclassification adjustment to net income, taxes	0	0	(289)	0
Less: amortization of prior service credit and net losses recognized during the period in net periodic benefit cost, tax benefits	(2,306)	(2,160)	(4,610)	(4,221)
Less: reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, taxes	$ 2,281	$ 2,166	$ 4,582	$ 4,218