Share-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Stock option
Share-Based Compensation
Exercise of stock options	6,807,859	4,814,173
Weighted average exercise price of options outstanding	$ 9.69	$ 9.52
Unrecognized compensation expenses related to options	$ 9.0	$ 14.8
Unrecognized compensation cost which is expected to be recognized over a weighted-average period	2 years 1 month 6 days	2 years 4 months 9 days
Vaccitech plc Share Award Plan 2021
Share-Based Compensation
Number of unvested options canceled	57,970	0
Vaccitech plc Share Award Plan 2021 \| Stock option
Share-Based Compensation
Options granted	1,987,289
Weighted-average grant date per-share fair value of stock options granted	$ 2.01
Weighted average exercise price of options granted	$ 2.53	$ 11.24
Vaccitech plc Share Award Plan 2021 \| Restricted share units, options, share appreciation rights and restricted shares
Share-Based Compensation
Percentage of issued and outstanding ordinary shares available for issuance under the Plan	4.00%
Enterprise Management Incentive Share Option Scheme \| Stock option
Share-Based Compensation
Options granted		1,632,922
Weighted-average grant date per-share fair value of stock options granted		$ 3.75

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

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Net 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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Number of options outstanding, including both vested and non-vested options.

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

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Total number of shares available for issuance under the Plan as a percentage of the Company's issued and outstanding shares.

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