Acquired Intangible Assets and Goodwill - Schedule of Goodwill (Details) $ in Thousands	6 Months Ended
Jun. 30, 2021 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2020	$ 9,186
Balance as of June 30, 2021	407,228
RentPath holdings
Goodwill [Roll Forward]
Goodwill resulting from acquisition	$ 398,042

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
-Name Accounting Standards Codification
-Topic 942
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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