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Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Federal corporate tax rate | 21.00% | 35.00%
Reclassification upon ASU implementation |  | $ 1,500
ASU 2018-02 [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification upon ASU implementation |  | 0
AOCI [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification upon ASU implementation |  | (2,600)
Retained Earnings [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification upon ASU implementation |  | 1,500
Other Assets [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification upon ASU implementation |  | 400
AOCI [Member] | ASU 2018-02 [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification upon ASU implementation |  | (5,575)
Retained Earnings [Member] | ASU 2018-02 [Member] |  |
New Accounting Pronouncements or Change in Accounting Principle [Line Items] |  |
Reclassification upon ASU implementation |  | $ 5,575

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