Consolidated Balance Sheets (Parenthetical) - £ / shares	Dec. 31, 2020	Dec. 31, 2019
Ordinary shares, nominal value	£ 0.01	£ 0.01
Ordinary shares, shares authorized	31,995,653	31,995,653
Ordinary shares, shares issued	21,094,557	17,993,701
Ordinary shares, shares outstanding	21,094,557	17,993,701

Face amount or stated value per share of common stock.

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- Definition

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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- Definition

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
-SubTopic 10
-Section 50
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