Share Incentive Plan - Summary of Share Option Plan Activity (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Number of Ordinary Shares
Outstanding balance	44,959,938
Granted	22,175,244
Cancelled or forfeited	(3,556,620)
Outstanding balance	63,578,562
Exercisable	32,701,811
Vested and expected to vest	60,345,324
Weighted-Average Exercise Price
Outstanding	$ 0.69
Granted	0.15
Cancelled or forfeited	0.64
Outstanding	0.50
Exercisable	0.71
Vested and expected to vest	$ 0.51
Average Remaining Contractual Life (in years)
Outstanding	7 years 4 months 24 days
Exercisable	6 years 3 months 18 days
Vested and expected to vest	7 years 4 months 24 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, outstanding		$ 11,650

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Share based compensation arrangement by share based payment award options intrinsic value abstract.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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.

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

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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