Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Goodwill [Roll Forward]
Goodwill balance at beginning of period	$ 335,433	$ 238,147
Effect of foreign exchange	(199)	(1,304)
Additions and adjustments as the result of acquisitions	17,959	98,590
Goodwill balance at end of period	$ 353,193	$ 335,433