Goodwill - Summary (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Goodwill [Roll Forward]
Goodwill at beginning of period	$ 458,586
Publica acquisition	191,721
Impact of exchange rates	(527)
Goodwill at end of period	$ 649,780

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

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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