Goodwill and Intangible Assets - Schedule of Goodwill Rollforward (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Goodwill [Roll Forward]
Beginning balance	$ 609,457	$ 609,457
Additions	72,051	0
Impairments		0
Effects of foreign currency translation	(5,068)
Ending balance	676,440	609,457
Marketing Services
Goodwill [Roll Forward]
Beginning balance	390,573	390,573
Additions	0	0
Impairments		0
Effects of foreign currency translation	0
Ending balance	390,573	390,573
SaaS
Goodwill [Roll Forward]
Beginning balance	218,884	218,884
Additions	0	0
Impairments		0
Effects of foreign currency translation	0
Ending balance	218,884	218,884
Thryv International
Goodwill [Roll Forward]
Beginning balance	0
Additions	72,051
Effects of foreign currency translation	(5,068)
Ending balance	$ 66,983	$ 0

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.

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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.

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