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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- Definition Amount of liability recognized arising from contingent consideration in a business combination. + References 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 + Details
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