Commitments and contingencies (Details) - GBP (£) £ in Millions |
Sep. 30, 2026 |
Mar. 31, 2026 |
|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | ||
| Energy purchase commitments | £ 16,785 | £ 16,757 |
| Contractual capital commitments | 7,271 | 6,909 |
| Capital commitments | 475 | £ 526 |
| Authorised capital commitments but not contracted for | £ 366 |
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- Definition The amount of capital commitments that have been authorised by the entity, but for which the entity has not entered into a contract. [Refer: Capital commitments] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of future capital expenditures that the entity is committed to make. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The amount of capital commitments for which the entity has entered into a contract. [Refer: Capital commitments] Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Energy Purchase Commitments No definition available.
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