Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Class Of Stock [Line Items]
Cash	$ 0
Deposits	71,000
Share Based Compensation Arrangement By Share Based Payment Award Fair Value Assumptions Expected Dividend Payments	0
Series B Redeemable Convertible Preferred Shares [Member]
Class Of Stock [Line Items]
Deferred finance costs, own-share lending arrangement, issuance costs, net	$ 0	$ 36,000

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 210
-Section 45
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of issuance costs recognized in a share-lending arrangement entered into by the entity, in contemplation of a convertible debt offering or other financing, after deduction of accumulated amortization or the effects of subsequent adjustments.

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Carrying value of amounts transferred to third parties for security purposes that are expected to be returned or applied towards payment after one year or beyond the operating cycle, if longer.

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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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