Stock Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount	$ 59,600,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition	3 years 1 month 28 days
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	9,564,798
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	6,308,582		6,316,569
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	6,404,001	8,756,005
Fair Value of Shares Vested	$ 3,600,000	$ 100,000
Share Based Compensation Number of Options Granted	93,973	0
Share Based Compensation Expected Dividend Yeild		$ 0
Shares Available for Future Equity Award Grants	9,556,911		7,928,031
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 33.32
Stock Option Awards [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Shares Available for Future Equity Award Grants	3,152,910
Unvested Common Stock [Member]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	76,293	5,095

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Aggregate number of common shares reserved for future issuance.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The estimated amount of dividends to be paid to holders of the underlying shares (expected dividends) over the option's term. Dividends are taken into account because payment of dividends to shareholders reduces the fair value of the underlying shares, and option holders generally do not receive dividends.

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Number of shares authorized for issuance under share-based payment arrangement.

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Gross number of share options (or share units) granted during the period.

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

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Number of options outstanding, including both vested and non-vested options.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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