Basis of Financial Statement Presentation - Accounting Pronouncements Adopted (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($)
ASU 2018-02
Reclassification from accumulated other comprehensive income to retained earnings	$ 66

Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act of 2017.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration