Income Taxes - Income Tax Uncertainties (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits, beginning	$ 1,127	$ 1,115	$ 788
Additions for prior year tax positions	41	50	454
Additions for current year tax positions	0	29	0
Lapse of statute of limitations	(248)	(67)	(102)
Reductions for tax positions of prior years	(14)	0	(25)
Unrecognized tax benefits, ending	$ 906	$ 1,127	$ 1,115

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Amount of unrecognized tax benefits.

+ References

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Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

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