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Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Loss Balance Sheet (Details) - USD ($) $ in Thousands | 9 Months Ended |
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Sep. 30, 2018 | Sep. 30, 2017 | Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax | $ 9,220 |  | $ 8,090
Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans Net Unamortized (Gain) Loss, Tax | 2,451 |  | $ 4,356
AOCI Attributable to Parent [Member] |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |
Reclassification of excess income tax benefits | $ (1,742) | $ 0 |

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- Definition Accumulated Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans Net Unamortized (Gain) Loss, Tax + References No definition available. + Details
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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 Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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