v3.21.2

Summary of Significant Accounting Policies - Balances of Financial Instruments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate swap, liabilities	$ (36,196)		$ (72,103)
Earnout liability	0	$ (10,063)	(7,509)	$ (13,177)	$ (37,975)	$ 0
Fair Value, Measurements, Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate swap, liabilities	(36,196)		(72,103)
Earnout liability			(7,509)
Fair Value, Measurements, Recurring | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Interest rate swap, liabilities	$ (36,196)
Fair Value, Measurements, Recurring | Fair Value Inputs Level3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Earnout liability			$ (7,509)

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6911189&loc=d3e6408-128476

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+ References

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