Aggregate number of common shares reserved for future issuance.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Amount of cost to be recognized for option under share-based payment arrangement.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Net number of non-option equity instruments granted to participants.

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Number of shares authorized for issuance under share-based payment arrangement.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Threshold annual increase to the number of ordinary shares reserved to percentage of number of ordinary shares outstanding.

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Share-based compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	9 Months Ended
	Aug. 31, 2017	Sep. 30, 2022	Jun. 22, 2022	Apr. 01, 2022
Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense related to unvested share options granted		$ 111.9
Recognized over a weighted-average period		3 years 5 months 19 days
Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Recognized over a weighted-average period		3 years 8 months 12 days
Unrecognized share-based compensation expense related to unvested restricted shares		$ 143.0
2017 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Threshold annual increase to the number of ordinary shares reserved as a percentage of number of ordinary shares outstanding	4.00%
Shares reserved under the plan (in shares)				75,562,170
Options granted (in shares)		19,357,640
Weighted-average grant-date fair value of options granted (in dollars per share)		$ 2.84
2017 Plan \| Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Contractual term		10 years
Vesting period		5 years
2017 Plan \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-option awards granted (in shares)		28,320,790
2017 Plan \| Tranche one \| Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Tranche two \| Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Tranche three \| Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Tranche four \| Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Tranche five \| Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price of options granted (in dollars per share)		$ 2.95
2017 Plan \| Minimum \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
2017 Plan \| Minimum \| Tranche one \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Minimum \| Tranche two \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Minimum \| Tranche three \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Minimum \| Tranche four \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Minimum \| Tranche five \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		20.00%
2017 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price of options granted (in dollars per share)		$ 6.29
2017 Plan \| Maximum \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		5 years
2017 Plan \| Maximum \| Tranche one \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		25.00%
2017 Plan \| Maximum \| Tranche two \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		25.00%
2017 Plan \| Maximum \| Tranche three \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		25.00%
2017 Plan \| Maximum \| Tranche four \| Non-vested restricted shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		25.00%
2022 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares authorized (in shares)			97,908,743