Deferred Acquisition Consideration (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 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			35,987		30,719
Redemption value adjustments	$ 1,816	$ 734	(759)	(6,100)	15,451
Additions			1,389		7,145
Foreign translation adjustment			(325)		196
Ending balance of contingent payments	38,989		38,989		74,671
Deferred acquisition consideration	39,252		39,252		75,220
Loss (Income) attributable to fair value adjustments	(2,312)	(2,073)	2,288	5,570
Stock-based compensation	(496)	(1,339)	1,529	(530)
Fixed payments
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Deferred acquisition consideration	263		263		$ 549
Contingent Payment
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Loss (Income) attributable to fair value adjustments	$ 2,312	$ 2,073	$ (2,288)	$ (5,570)

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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

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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- Definition

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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