Deferred Acquisition Consideration (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance of contingent payments	$ 82,802	$ 74,671	$ 74,671
Payments	1,153		46,792
Redemption value adjustments	12,392	(2,575)	44,993
Additions	0		7,703
Foreign translation adjustment	(641)		2,227
Ending balance of contingent payments	93,400		82,802
Deferred acquisition consideration	93,400		83,065
Stock-based compensation	707	2,025
Fixed payments
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Deferred acquisition consideration	0		$ 263
Contingent Payment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loss (income) attributable to fair value adjustments	$ 11,685	$ (4,600)

Adjustments to deferred acquisition consideration included in share-based compensation

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Amount of foreign currency translation adjustment arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

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Amount of increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

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Amount of liability recognized arising from contingent consideration in a business combination.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3).

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Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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