Fair Value Measurements - Summary of Changes in Level 3 Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Beginning balance, fair value	$ 10,619
Ending balance, fair value	19,331	$ 2,530
Foreign currency translation	(465)
Connexient
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Contingent consideration		340
One2Many Group B.V.
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Contingent consideration		$ 2,190
Adjustment for acquisition	(690)
Red Sky Technologies Inc.
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Contingent consideration	9,135
SnapComms Limited
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Adjustment for acquisition	$ 732

Fair value, measurement with unobservable inputs reconciliation, recurring basis, liability, adjustments.

No definition available.

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- Definition

Fair value measurement with unobservable inputs reconciliation recurring basis liability foreign currency translation.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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