Consolidated Balance Sheets (Parenthetical)	Dec. 31, 2021 £ / shares shares	Dec. 31, 2021 $ / shares shares	Dec. 31, 2020 £ / shares shares	Dec. 31, 2020 $ / shares shares
Ordinary shares, par value \| (per share)	£ 0.001	$ 0.001	£ 0.001	$ 0.001
Ordinary shares, shares authorized	40,603,489	40,603,489	4,389,920	4,389,920
Ordinary shares, shares issued	40,603,489	40,603,489	4,389,920	4,389,920
Ordinary shares, shares outstanding	40,603,489	40,603,489	4,389,920	4,389,920
Deferred shares, par value \| £ / shares	£ 92,451.851		£ 0.001
Deferred shares, shares authorized	1	1
Deferred shares, shares issued	1	1	30,521	30,521
Deferred shares, shares outstanding	1	1	30,521	30,521
Convertible Preferred Shares
Convertible preferred shares, par value \| £ / shares	£ 0.001		£ 0.001
Convertible preferred shares, shares authorized	0	0	104,854,673	104,854,673
Convertible preferred shares, shares issued	0	0	104,854,673	104,854,673
Convertible preferred shares, shares outstanding	0	0	104,854,673	104,854,673

Deferred shares, authorized.

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Deferred shares, issued.

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Deferred shares, outstanding.

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Deferred shares, par or stated value per share.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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