Fair value measurements - Summary of Warrants Measured at Fair Value (Detail) - $ / shares	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Schedule Of Warrants Were Measured at Fair Value [Line Items]
Dividend yield	0.00%
Warrant [Member]
Schedule Of Warrants Were Measured at Fair Value [Line Items]
Exercise price		$ 9.32
Term (in years)		3 months 25 days
Risk-free interest rate		0.10%
Dividend yield		0.00%
Volatility		120.00%

Schedule Of Warrants Were Measured at Fair Value [Line Items]

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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 14.D.2)
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