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New Accounting Standards New Accounting Standards (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Document Period End Date |  | Jun. 30, 2018 |
AOCI Attributable to Parent [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Reclassification of excess income tax benefits |  | $ (1,742) | $ 0
Restatement Adjustment [Member] |  |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |  |
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) | $ 1,800 |  | $ 3,900

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- Definition Reclassification from AOCI to Retained Earnings -ASU 2018-02 was issued February 2018, which allows stranded tax effects associated with the enactment of the Tax Cuts and Jobs Act to be reclassified from AOCI to Retained Earnings. + References No definition available. + Details
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- Definition The end date of the period reflected on the cover page if a periodic report. For all other reports and registration statements containing historical data, it is the date up through which that historical data is presented. If there is no historical data in the report, use the filing date. The format of the date is CCYY-MM-DD. + References No definition available. + Details
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 + Details
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