Statement Of Changes In Equity [Abstract]

Serco Group PLC - Filing #2006913

Concept	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31
Statement of changes in equity [abstract]
Statement of changes in equity [line items]
Increase (decrease) through exercise of options, equity	—	—	—	—	—	—	—	— GBP	100,000 GBP	100,000 GBP	— GBP	— GBP	— GBP
Purchase of treasury shares	— GBP	—	— GBP	— GBP	— GBP	88,800,000 GBP	88,800,000 GBP	— GBP	91,200,000 GBP	91,200,000 GBP	— GBP	— GBP	— GBP
Cancellation of treasury shares	2,300,000 GBP	— GBP	—	180,000,000 GBP	— GBP	— GBP	182,300,000 GBP	—	—	—	—	—	—