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New Accounting Pronouncements (Details) - Accounting Standards Update 2018-02 $ in Thousands | 3 Months Ended
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Mar. 31, 2018 USD ($)
Accumulated Other Comprehensive Income (Loss) |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Reclassification from AOCI to retained earnings | $ (1,772)
Retained Earnings |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |
Reclassification from AOCI to retained earnings | $ 1,772

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