Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Goodwill balance at beginning of period	$ 353,193	$ 335,433
Effect of foreign exchange	1,941	(199)
Additions and adjustments as the result of acquisitions	8,399	17,959
Goodwill balance at end of period	$ 363,533	$ 353,193