Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2021-12-31 |
As at 2020-12-31 |
|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | ||
| Property, plant and equipment [abstract] | ||
| Property, plant and equipment |
398. 1
GBP
|
402. 7
GBP
|
| Intangible assets and goodwill [abstract] | ||
| Intangible assets and goodwill |
2, 164.3
GBP
|
1,922. 1
GBP
|
| Investments in subsidiaries, joint ventures and associates reported in separate financial statements [abstract] | ||
| Investments in associates reported in separate financial statements |
2 9 .7
GBP
|
27 .2
GBP
|
| Trade and other non-current receivables [abstract] | ||
| Trade and other non-current receivables |
14,300,000
GBP
|
13. 1
GBP
|
| Non-current prepayments and non-current accrued income including non-current contract assets [abstract] | ||
| Non-current accrued income including non-current contract assets [abstract] | ||
| Non-current contract assets |
75,000,000
GBP
|
67 .8
GBP
|
| Miscellaneous non-current assets [abstract] | ||
| Non-current derivative financial assets |
9,800,000
GBP
|
3 7. 0
GBP
|
| Trade and other receivables [abstract] | ||
| Trade and other receivables |
526,900,000
GBP
|
56 9.6
GBP
|
| Categories of non-current financial assets [abstract] | ||
| Non-current financial assets at fair value through profit or loss [abstract] | ||
| Non-current financial assets at fair value through profit or loss, designated upon initial recognition or subsequently |
200,000
GBP
|
200,000
GBP
|
| Cash and cash equivalents [abstract] | ||
| Cash and cash equivalents |
668,400,000
GBP
|
1,949,500,000
GBP
|
| Miscellaneous current assets [abstract] | ||
| Current investments | — | — |
| Short-term deposits, not classified as cash equivalents |
1 .6
GBP
|
172,200,000
GBP
|
| Miscellaneous assets [abstract] | ||
| Net defined benefit asset |
19,000,000
GBP
|
1 9.0
GBP
|
| Derivative financial assets |
2,500,000
GBP
|
5 .6
GBP
|
| Borrowings [abstract] | ||
| Non-current portion of non-current borrowings |
1,256. 1
GBP
|
1,337 .6
GBP
|
| Current borrowings and current portion of non-current borrowings [abstract] | ||
| Current borrowings |
459,300,000
GBP
|
1,591,500,000
GBP
|
| Non-current portion of non-current borrowings, by type [abstract] | ||
| Trade and other payables [abstract] | ||
| Trade and other payables |
764,000,000
GBP
|
925,000,000
GBP
|
| Miscellaneous non-current liabilities [abstract] | ||
| Non-current net defined benefit liability |
27 .3
GBP
|
38,800,000
GBP
|
| Non-current derivative financial liabilities |
33,500,000
GBP
|
32,300,000
GBP
|
| Miscellaneous current liabilities [abstract] | ||
| Current derivative financial liabilities |
1,000,000
GBP
|
3,500,000
GBP
|
| Issued capital [abstract] | ||
| Issued capital |
18,600,000
GBP
|
18,500,000
GBP
|
| Retained earnings [abstract] | ||
| Retained earnings |
3, 166.6
GBP
|
3,0 3 0.6
GBP
|
| Net assets (liabilities) [abstract] | ||
| Assets (liabilities) |
1,263,900,000
GBP
|
1, 130. 6
GBP
|
| Net current assets (liabilities) [abstract] | ||
| Current assets |
1,343,600,000
GBP
|
2,838,800,000
GBP
|
| Current liabilities |
1,389. 6
GBP
|
2, 702.8
GBP
|
| Current assets (liabilities) |
46,000,000
GBP
|
136. 0
GBP
|
| Assets less current liabilities [abstract] |