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Consolidated Statements of Comprehensive Income Parenthetical - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Statement of Comprehensive Income [Abstract] |  |
Amortization of actuarial loss, tax | $ 208 | $ 152

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- Definition Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan. + 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=84228862&loc=d3e640-108580 + Details
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- References No definition available. + Details
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