Deferred Acquisition Consideration (Details) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance of contingent payments	$ 74,671	$ 82,598	$ 82,598
Payments	1,125		30,719
Redemption value adjustments	(2,575)	(6,834)	15,451
Additions	1,389		7,145
Foreign translation adjustment	(185)		196
Ending balance of contingent payments	72,175		74,671
Deferred acquisition consideration	72,736		75,220
Stock-based compensation	2,025	809
Fixed payments
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Deferred acquisition consideration	561		$ 549
Contingent Payment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Income attributable to fair value adjustments	$ (4,600)	$ (7,643)