Share-Based Compensation - Summary of Stock Option Activity (Detail)	12 Months Ended
Dec. 31, 2021 shares
Number of Shares
Outstanding as of December 31, 2020	3,682,233
Granted	1,708,709
Exercised	(160,674)
Forfeited or cancelled	(339,552)
Outstanding as of December 31, 2021	4,890,716
2017 Plan [Member]
Number of Shares
Outstanding as of December 31, 2020	3,137,233
Granted	1,161,309
Exercised	(140,537)
Forfeited or cancelled	(264,400)
Outstanding as of December 31, 2021	3,893,605
2019 Inducement Plan [Member]
Number of Shares
Outstanding as of December 31, 2020	545,000
Granted	547,400
Exercised	(20,137)
Forfeited or cancelled	(75,152)
Outstanding as of December 31, 2021	997,111

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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

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No definition available.

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Number of share options (or share units) exercised during the current period.

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