Statement Of Cash Flows [Abstract]
| Concept |
As at 2023-09-30 |
2022-10-01 to 2023-09-30 |
2021-10-01 to 2022-09-30 |
As at 2022-09-30 |
As at 2021-09-30 |
|---|---|---|---|---|---|
| Statement of cash flows [abstract] | |||||
| Cash flows from (used in) operating activities [abstract] | |||||
| Classes of cash payments from operating activities [abstract] | |||||
| Payments to and on behalf of employees | — |
300,000
GBP
|
600,000
GBP
|
— | — |
| Cash flows from (used in) operations | — |
229,200,000
GBP
|
156,900,000
GBP
|
— | — |
| Interest paid, classified as operating activities | — |
46,900,000
GBP
|
42,000,000
GBP
|
— | — |
| Income taxes paid (refund), classified as operating activities | — |
2,700,000
GBP
|
12,300,000
GBP
|
— | — |
| Cash flows from (used in) operating activities | — |
184,700,000
GBP
|
102,000,000
GBP
|
— | — |
| Cash flows from (used in) investing activities [abstract] | |||||
| Other cash payments to acquire interests in joint ventures, classified as investing activities | — |
34,000,000
GBP
|
6,400,000
GBP
|
— | — |
| Cash flows from (used in) investing activities | — |
274,100,000
GBP
|
274,200,000
GBP
|
— | — |
| Cash flows from (used in) financing activities [abstract] | |||||
| Payments to acquire or redeem entity's shares | — |
7,900,000
GBP
|
3,300,000
GBP
|
— | — |
| Proceeds from borrowings, classified as financing activities | — |
330,000,000
GBP
|
14,200,000
GBP
|
— | — |
| Repayments of borrowings, classified as financing activities | — |
155,000,000
GBP
|
900,000
GBP
|
— | — |
| Dividends paid, classified as financing activities | — |
45,700,000
GBP
|
40,000,000
GBP
|
— | — |
| Cash flows from (used in) financing activities | — |
114,500,000
GBP
|
49,500,000
GBP
|
— | — |
| Increase (decrease) in cash and cash equivalents after effect of exchange rate changes | — |
25,100,000
GBP
|
221,700,000
GBP
|
— | — |
| Cash and cash equivalents |
121,000,000
GBP
|
— | — |
95,900,000
GBP
|
317,600,000
GBP
|