Description of Business and Summary of Significant Accounting Policies - Contract Liabilities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Balance, beginning of period	$ 37,253	$ 44,660
Revenue recognized from beginning balance	(32,783)	(31,507)
Additions from business acquisitions	0	769
Additions, net of revenue recognized and currency translation	36,460	23,331
Balance, end of period	$ 40,930	$ 37,253