Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Beginning balance	$ 8,771	$ 5,772	$ 4,882
Increase in tax positions for prior years	221	758	280
Decrease in tax positions for prior years	(1,550)	(569)	(101)
Decrease in tax positions for prior year settlement	0	(149)	(172)
Decrease in tax positions for prior years due to statutes lapsing	(164)	(103)	(169)
Increase in tax positions for current year	3,722	3,112	978
Change due to translation of foreign currencies	(7)	(50)
Ending balance	$ 10,993	$ 8,771	5,772
Unrecognized Tax Benefits, Increase Resulting from Foreign Currency Translation			$ 74

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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Amount of unrecognized tax benefits.

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