Statement Of Changes In Equity [Abstract]

Babcock International Group PLC - Filing #2067746

Concept	As at 2024-03-31	As at 2024-03-31	2023-04-01 to 2024-03-31	As at 2024-03-31	2023-04-01 to 2024-03-31	As at 2024-03-31	2023-04-01 to 2024-03-31	As at 2024-03-31	As at 2024-03-31	As at 2024-03-31	As at 2024-03-31	2023-04-01 to 2024-03-31	As at 2024-03-31	2023-04-01 to 2024-03-31	2023-04-01 to 2024-03-31	2023-04-01 to 2024-03-31	2023-04-01 to 2024-03-31	2023-04-01 to 2024-03-31	2023-04-01 to 2024-03-31	As at 2024-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31	2022-04-01 to 2023-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31	As at 2022-03-31
Statement of changes in equity [abstract]
Statement of changes in equity [line items]
Equity	388,900,000 GBP	5,300,000 GBP	—	768,800,000 GBP	—	1,523. 9 GBP	—	17,200,000 GBP	873,000,000 GBP	303,400,000 GBP	30,600,000 GBP	—	406,100,000 GBP	—	—	—	—	—	—	68,300,000 GBP	—	—	353,900,000 GBP	3,000,000 GBP	768,800,000 GBP	—	—	370,900,000 GBP	873,000,000 GBP	303,400,000 GBP	30,600,000 GBP	—	—	—	—	—	1,568,800,000 GBP	17,000,000 GBP	56,100,000 GBP	—	30,600,000 GBP	303,400,000 GBP	682,000,000 GBP	768,800,000 GBP	4,000,000 GBP	56,400,000 GBP	1,241,400,000 GBP	19,500,000 GBP	873,000,000 GBP	701,500,000 GBP
Changes in equity [abstract]
Comprehensive income [abstract]
Profit (loss)	—	—	– GBP	—	– GBP	—	165,700,000 GBP	—	—	—	—	168,200,000 GBP	—	– GBP	– GBP	– GBP	165,700,000 GBP	2,500,000 GBP	– GBP	—	– GBP	35,000,000 GBP	—	—	—	– GBP	– GBP	—	—	—	—	– GBP	– GBP	– GBP	35,000,000 GBP	1,700,000 GBP	—	—	—	33,300,000 GBP	—	—	—	—	—	—	—	—	—	—
Other comprehensive income	—	—	2,300,000 GBP	—	– GBP	—	126,600,000 GBP	—	—	—	—	127,800,000 GBP	—	– GBP	– GBP	– GBP	116,700,000 GBP	1,200,000 GBP	12,200,000 GBP	—	– GBP	302,300,000 GBP	—	—	—	– GBP	1,000,000 GBP	—	—	—	—	300,000 GBP	– GBP	– GBP	301,600,000 GBP	2,000,000 GBP	—	—	—	304,300,000 GBP	—	—	—	—	—	—	—	—	—	—
Comprehensive income	—	—	2,300,000 GBP	—	– GBP	—	39,100,000 GBP	—	—	—	—	40,400,000 GBP	—	– GBP	– GBP	– GBP	49,000,000 GBP	1,300,000 GBP	12,200,000 GBP	—	– GBP	337,300,000 GBP	—	—	—	– GBP	1,000,000 GBP	—	—	—	—	300,000 GBP	– GBP	– GBP	336,600,000 GBP	300,000 GBP	—	—	—	337,600,000 GBP	—	—	—	—	—	—	—	—	—	—
Dividends recognised as distributions to owners	—	—	– GBP	—	– GBP	—	8,500,000 GBP	—	—	—	—	10,300,000 GBP	—	– GBP	– GBP	– GBP	8,500,000 GBP	1,800,000 GBP	– GBP	—	– GBP	– GBP	—	—	—	– GBP	– GBP	—	—	—	—	– GBP	– GBP	– GBP	– GBP	2,200,000 GBP	—	—	—	2,200,000 GBP	—	—	—	—	—	—	—	—	—	—
Increase (decrease) through share-based payment transactions, equity	—	—	– GBP	—	– GBP	—	12,400,000 GBP	—	—	—	—	12,400,000 GBP	—	– GBP	– GBP	– GBP	12,400,000 GBP	– GBP	– GBP	—	– GBP	9,400,000 GBP	—	—	—	– GBP	– GBP	—	—	—	—	– GBP	– GBP	– GBP	9,400,000 GBP	– GBP	—	—	—	9,400,000 GBP	—	—	—	—	—	—	—	—	—	—
Increase (decrease) in equity	—	—	2,300,000 GBP	—	– GBP	—	35,000,000 GBP	—	—	—	—	35,200,000 GBP	—	– GBP	– GBP	– GBP	44,900,000 GBP	200,000 GBP	12,200,000 GBP	—	– GBP	328,100,000 GBP	—	—	—	– GBP	1,000,000 GBP	—	—	—	—	300,000 GBP	– GBP	– GBP	327,400,000 GBP	2,500,000 GBP	—	—	—	330,600,000 GBP	—	—	—	—	—	—	—	—	—	—