Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	6 Months Ended	12 Months Ended
	Jan. 01, 2025	Feb. 28, 2025	Jun. 30, 2025	Dec. 31, 2024	Jan. 10, 2025
Subsequent Event [Line Items]
Number of options granted (in shares)				2,170,352
Weighted average exercise price of options granted (in usd per share)				$ 3.17
Subsequent Event
Subsequent Event [Line Items]
Expected pre-tax costs related to workforce reduction					$ 2.5
Number of options granted (in shares)		1,341,802
Weighted average exercise price of options granted (in usd per share)		$ 1.00
Subsequent Event | Forecast
Subsequent Event [Line Items]
Percentage reduction in headcount			65.00%
Barinthus Biotherapeutics plc Share Award Plan 2021 | Subsequent Event
Subsequent Event [Line Items]
Percentage of issued and outstanding ordinary shares available for issuance	4.00%