Share-Based Compensation - Summary of Stock Option Activity (Detail)	12 Months Ended
Dec. 31, 2022 shares
Number of Shares
Outstanding as of December 31, 2021	4,890,716
Granted	956,604
Exercised	(56,120)
Forfeited or cancelled	(1,812,101)
Outstanding as of December 31, 2022	3,979,099
2017 Plan [Member]
Number of Shares
Outstanding as of December 31, 2021	3,893,605
Granted	956,604
Exercised	(56,120)
Forfeited or cancelled	(1,161,257)
Outstanding as of December 31, 2022	3,632,832
2019 Inducement Plan [Member]
Number of Shares
Outstanding as of December 31, 2021	997,111
Forfeited or cancelled	(650,844)
Outstanding as of December 31, 2022	346,267

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(02)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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