Number of outstanding shares cancelled.

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- Definition

Share based compensation arrangement by share based payment award increase of reserved shares percent of ordinary shares outstanding.

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No definition available.

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- Definition

Share-based compensation arrangement by share bases payment award remaining vesting period.

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No definition available.

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- Definition

Stock repurchase price per share.

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No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Paragraph 1
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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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-Section 50
-Paragraph 2
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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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- Definition

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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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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No definition available.

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- Definition

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

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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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Number of shares issued under share-based payment arrangement.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Share-based Compensation - Additional Information (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) £ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2021 shares	Dec. 31, 2020 £ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period	4 years
Remaining vesting period	3 years
Unrecognized compensation costs related to unvested employee shares outstanding \| $	$ 11.3	$ 17.4	$ 17.4
Weighted-average period	2 years 7 months 6 days	3 years 1 month 6 days	3 years 1 month 6 days
Weighted average grant-date fair value of share options granted \| $ / shares	$ 5.42		$ 3.33
Unrecognized compensation cost related to share options outstanding \| $	$ 5.4
Share Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average period	3 years 3 months 18 days
Deferred Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Deferred share repurchased	1	1,509,384	1,509,384
Stock repurchase price per share \| £ / shares		$ 0.01
Number of outstanding shares cancelled		109,058	109,058
Price per share \| £ / shares					£ 92,451.851
Vesting on First Anniversary
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage	25.00%
2021 Share Omnibus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ordinary shares reserved for future issuance				2,572,558
Increase of reserved shares, percent of common stock outstanding	4.00%
Ordinary shares issued	2,572,558
Shares available for future grant	1,578,993
2021 Employee Share Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Increase of reserved shares, percent of common stock outstanding	1.00%
Ordinary shares issued	467,738
Shares available for future grant	467,738
2021 Employee Share Purchase Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ordinary shares authorized for issuance				467,738