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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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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Price of a single share of a number of saleable stocks of a company.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	3 months
2013 Amended And Restated Stock Performance Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement number of shares authorized	4,179,202
Common stock shares reserved for future issuance	483,681
Share price	$ 16.00		$ 0.83
Share based compensation by share based payment arrangement weighted average grant date fair value of options granted	$ 1.34
Share based compensation by share based payment arrangement non vested options granted during the period	2,663,084	0
Share based compensation by share based payment arrangement unrecognized compensation costs non vested options	$ 3.4
Share based compensation by share based payment arrangement unrecognized compensation costs weighted aveage period of recognition	3 years 3 months 18 days
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted After December 31, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement contractual term	10 years
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted After December 31, 2017 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	24 months
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted After December 31, 2017 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	36 months
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted Before December 31, 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement contractual term	10 years
2013 Amended And Restated Stock Performance Plan [Member] \| Stock Options Granted Before December 31, 2017 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation by share based payment arrangement vesting period	24 months