v3.21.2

Summary of Significant Accounting Policies - Summary of Reconciliation of Change in Earnout Liability (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2021		Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value Disclosures [Abstract]
Beginning balance	$ 10,063		$ 37,975	$ 7,509	$ 0
Allocation of Internalization purchase price at February 7, 2020					40,119
Change in fair value subsequent to Internalization	1,059	[1]	(6,362)	5,539	(8,506)
Reclassification as a component of additional paid-in capital and non-controlling interests			(18,436)		(18,436)
Payout of tranches earned	(11,122)			(13,048)
Ending balance	$ 0		$ 13,177	$ 0	$ 13,177
[1] The $1,059 change in fair value during the three months ended September 30, 2021, represented the difference between the actual cash payments subsequent to June 30, 2021, and the earnout liability's fair value at June 30, 2021.

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Amount of liability recognized arising from contingent consideration in a business combination.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 35
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=116859824&loc=d3e6819-128478

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 25
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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