Income Taxes - Uncertain Tax Positions - Tabular Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized Tax Benefits, Beginning Balance	$ 19,097	$ 7,050	$ 6,761
Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions	2,025
Decrease in unrecognized tax benefits taken in prior periods		(28)	(183)
Increase in Unrecognized Tax Benefits Taken in Current Period	3,095	1,935	2,023
Decrease in Unrecognized Tax Benefits Due to Lapse of Statute of Limitations	(3,659)	(1,029)	(1,292)
Increase in unrecognized tax benefits due to acquisition	597	11,301	0
(Decrease) Due to Foreign Exchange Rates		(132)	(259)
Increase Due to Foreign Exchange Rates	997
Unrecognized Tax Benefits, Ending Balance	$ 22,152	$ 19,097	$ 7,050