Statement Of Cash Flows [Abstract]
| Concept |
2021-01-01 to 2021-12-31 |
2020-01-01 to 2020-12-31 |
|---|---|---|
| Statement of cash flows [abstract] | ||
| Cash flows from (used in) operating activities [abstract] | ||
| Income taxes paid, classified as operating activities |
68,900,000
GBP
|
64,400,000
GBP
|
| Cash flows from (used in) investing activities [abstract] | ||
| Cash flows from (used in) decrease (increase) in short-term deposits and investments |
17 0.6
GBP
|
170,500,000
GBP
|
| Cash flows from (used in) financing activities [abstract] | ||
| Dividends paid to equity holders of parent, classified as financing activities |
138. 7
GBP
|
— |