v3.21.2

Stock-Based Compensation - Summary of RSAs (Detail) - Restricted Stock Awards - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation cost	$ 701	$ 796	$ 3,124	$ 796
Dividends declared on unvested RSAs	95	46	296	46
Grant date fair value of shares vested during the period	0	$ 0	3,296	$ 0
Unamortized value of RSAs	$ 5,508		$ 5,508		$ 5,001
Weighted average amortization period (in years)			2 years 7 months 6 days		2 years 9 months 18 days

X

- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

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-Publisher FASB
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-Topic 718
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+ References

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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