Statement Of Cash Flows [Abstract]
| Concept |
As at 2024-09-30 |
2023-10-01 to 2024-09-30 |
As at 2023-09-30 |
2022-10-01 to 2023-09-30 |
As at 2022-09-30 |
|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||
| Cash flows from (used in) operating activities [abstract] | |||||
| Cash flows from (used in) operating activities | — |
3,307,000,000
GBP
|
— |
3,129,000,000
GBP
|
— |
| Cash flows from (used in) investing activities [abstract] | |||||
| Purchase of intangible assets, classified as investing activities | — |
42,000,000
GBP
|
— |
183,000,000
GBP
|
— |
| Purchase of other long-term assets, classified as investing activities | — |
371,000,000
GBP
|
— |
325,000,000
GBP
|
— |
| Interest received, classified as investing activities | — |
15,000,000
GBP
|
— |
10,000,000
GBP
|
— |
| Cash flows from (used in) investing activities | — |
348,000,000
GBP
|
— |
427,000,000
GBP
|
— |
| Cash flows from (used in) financing activities [abstract] | |||||
| Proceeds from borrowings, classified as financing activities | — |
3,848,000,000
GBP
|
— |
1,462,000,000
GBP
|
— |
| Repayments of borrowings, classified as financing activities | — |
3,948,000,000
GBP
|
— |
1,518,000,000
GBP
|
— |
| Payments of lease liabilities, classified as financing activities | — |
93,000,000
GBP
|
— |
92,000,000
GBP
|
— |
| Interest paid, classified as financing activities | — |
431,000,000
GBP
|
— |
417,000,000
GBP
|
— |
| Cash flows from (used in) financing activities | — |
3,162,000,000
GBP
|
— |
3,051,000,000
GBP
|
— |
| Increase (decrease) in cash and cash equivalents before effect of exchange rate changes | — |
203,000,000
GBP
|
— |
349,000,000
GBP
|
— |
| Effect of exchange rate changes on cash and cash equivalents [abstract] | |||||
| Effect of exchange rate changes on cash and cash equivalents | — |
64,000,000
GBP
|
— |
156,000,000
GBP
|
— |
| Cash and cash equivalents |
1,078,000,000
GBP
|
— |
1,345,000,000
GBP
|
— |
1,850,000,000
GBP
|