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Condensed Consolidated Statements of Comprehensive Income (unaudited) (Parenthetical) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Statement of Comprehensive Income [Abstract] |  |
Net unrealized gains (losses) on securities arising during the period, taxes (benefits) | $ (4,867) | $ 148
Reclassification adjustment to net income, tax expense (benefits) | 0 | (289)
Amortization of prior service credit and net losses recognized during the period in net periodic benefit cost, taxes (benefits) | (1,792) | (2,502)
Reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, taxes | 1,603 | 2,301
Hawaiian Electric Company, Inc. and Subsidiaries |  |
Reclassification adjustment to net income, tax expense (benefits) | 0 | (289)
Amortization of prior service credit and net losses recognized during the period in net periodic benefit cost, taxes (benefits) | (1,614) | (2,304)
Reclassification adjustment for impact of D&Os of the PUC included in regulatory assets, taxes | $ 1,603 | $ 2,301

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- Definition The amount of income taxes on the reclassification adjustments on pension and post retirement benefits for the accounting impact of the decisions issued by the Public Utilities Commission. + References No definition available. + Details
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- Definition Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income of accumulated gain (loss) realized from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's deferred hedging gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph c -URI http://asc.fasb.org/extlink&oid=64837297&loc=d3e41638-113959 + Details
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- Definition Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans. + References No definition available. + Details
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- Definition Amount of tax expense (benefit) before reclassification adjustments of unrealized holding gain (loss) on available-for-sale securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=66004124&loc=d3e640-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (e,f) -URI http://asc.fasb.org/extlink&oid=66004124&loc=SL7669646-108580 + Details
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