Share-Based Compensation - Summary of Stock Option Activity (Detail)	12 Months Ended
Dec. 31, 2023 shares
Number of Shares
Outstanding as of December 31, 2022	3,979,099
Granted	46,413
Exercised	0
Forfeited or cancelled	(1,159,918)
Outstanding as of December 31, 2023	2,865,594
2017 Plan [Member]
Number of Shares
Outstanding as of December 31, 2022	3,632,832
Granted	46,413
Exercised	0
Forfeited or cancelled	(1,109,824)
Outstanding as of December 31, 2023	2,569,421
2019 Inducement Plan [Member]
Number of Shares
Outstanding as of December 31, 2022	346,267
Forfeited or cancelled	(50,094)
Outstanding as of December 31, 2023	296,173

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
-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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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://fasb.org/us-gaap/role/ref/legacyRef
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