Equity Based Awards - Summary of Additional Information Regarding Exercise of Stock Options (Detail) - 2013 Stock Plan [Member] - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Share Based Compensation Arrangement By Share Based Payment Award Options Additional Disclosures [Line Items]
Weighted-average grant date fair value of options granted	$ 0	$ 1.02
Intrinsic value of options exercised	$ 16,496	$ 3,158

Share Based Compensation Arrangement By Share Based Payment Award Options Additional Disclosures

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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