Income Taxes - Tax Contingency (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]
Balance, January 1	$ 2,284	$ 2,691	$ 3,137
Changes for tax positions of prior years, decrease	(861)	(16)
Changes for tax positions of prior years, increase			580
Increases for tax positions related to the current year	165	138	181
Settlements and lapsing of statutes of limitations	0	(529)	(1,207)
Balance, December 31	$ 1,588	$ 2,284	$ 2,691

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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