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Accounting Policies - Income Taxes (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2017 USD ($)
Accounting Policies [Abstract] |
Reclass of Stranded Tax Effects from AOCI to Retained Earnings | $ 0

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- Definition Reclass of Stranded Tax Effects from AOCI to Retained Earnings related to ASU 2018-02 + References No definition available. + Details
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- References No definition available. + Details
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