Statement Of Changes In Equity [Abstract]

Severn Trent PLC - Filing #7157676

Concept	As at 2025-03-31	As at 2025-03-31	2024-04-01 to 2025-03-31	As at 2025-03-31	2024-04-01 to 2025-03-31	As at 2025-03-31	As at 2025-03-31	2024-04-01 to 2025-03-31	2024-04-01 to 2025-03-31	2024-04-01 to 2025-03-31	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	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31	As at 2023-03-31
Statement of changes in equity [abstract]
Statement of changes in equity [line items]
Equity	174,300,000 GBP	1,770,800,000 GBP	—	1,378,300,000 GBP	—	296,300,000 GBP	78,100,000 GBP	—	—	—	—	167,600,000 GBP	7,900,000 GBP	1,363,100,000 GBP	295,400,000 GBP	—	1,834,000,000 GBP	—	—	—	970,600,000 GBP	408,700,000 GBP	249,100,000 GBP	162,500,000 GBP	150,300,000 GBP
Changes in equity [abstract]
Comprehensive income [abstract]
Profit (loss)	—	—	229,400,000 GBP	—	229,400,000 GBP	—	—	– GBP	– GBP	– GBP	– GBP	—	—	—	—	140,200,000 GBP	—	– GBP	– GBP	140,200,000 GBP	—	—	—	—	—
Other comprehensive income	—	—	35,100,000 GBP	—	—	—	—	—	—	—	—	—	—	—	—	21,200,000 GBP	—	—	—	—	—	—	—	—	—
Comprehensive income	—	—	264,500,000 GBP	—	257,800,000 GBP	—	—	– GBP	– GBP	6,700,000 GBP	9,000,000 GBP	—	—	—	—	161,400,000 GBP	—	– GBP	– GBP	152,400,000 GBP	—	—	—	—	—
Issue of equity	—	—	1,800,000 GBP	—	1,800,000 GBP	—	—	– GBP	– GBP	– GBP	—	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Dividends recognised as distributions to owners	—	—	356,000,000 GBP	—	356,000,000 GBP	—	—	– GBP	– GBP	– GBP	– GBP	—	—	—	—	301,400,000 GBP	—	– GBP	– GBP	301,400,000 GBP	—	—	—	—	—