Subclassifications Of Assets, Liabilities And Equities [Abstract]
| Concept |
As at 2021-12-31 |
As at 2020-12-31 |
As at 2019-12-31 |
|---|---|---|---|
| Subclassifications of assets, liabilities and equities [abstract] | |||
| Property, plant and equipment [abstract] | |||
| Property, plant and equipment |
90,000,000
GBP
|
107,000,000
GBP
|
— |
| Intangible assets and goodwill [abstract] | |||
| Intangible assets and goodwill |
273,700,000
GBP
|
274,700,000
GBP
|
— |
| Investments in subsidiaries, joint ventures and associates reported in separate financial statements [abstract] | |||
| Investments in associates reported in separate financial statements |
100,000
GBP
|
100,000
GBP
|
— |
| Trade and other non-current receivables [abstract] | |||
| Non-current prepayments and non-current accrued income other than non-current contract assets [abstract] | |||
| Non-current prepayments |
16,600,000
GBP
|
23,600,000
GBP
|
— |
| Non-current prepayments and non-current accrued income including non-current contract assets [abstract] | |||
| Trade and other current receivables [abstract] | |||
| Current prepayments and current accrued income other than current contract assets [abstract] | |||
| Current prepayments [abstract] | |||
| Current prepayments |
103,000,000
GBP
|
102,800,000
GBP
|
— |
| Current prepayments and current accrued income including current contract assets [abstract] | |||
| Trade and other receivables [abstract] | |||
| Trade and other receivables |
1,275,200,000
GBP
|
1,095,900,000
GBP
|
— |
| Classes of current inventories [abstract] | |||
| Current inventories |
341,300,000
GBP
|
211,300,000
GBP
|
— |
| Classes of current inventories, alternative [abstract] | |||
| Cash and cash equivalents [abstract] | |||
| Cash [abstract] | |||
| Cash |
285,200,000
GBP
|
309,800,000
GBP
|
— |
| Cash and cash equivalents |
273,200,000
GBP
|
309,800,000
GBP
|
217,800,000
GBP
|
| Miscellaneous current assets [abstract] | |||
| Current derivative financial assets |
3,600,000
GBP
|
1,600,000
GBP
|
— |
| Trade and other current payables [abstract] | |||
| Trade and other current payables |
1,410,400,000
GBP
|
1,116,700,000
GBP
|
— |
| Categories of non-current financial liabilities [abstract] | |||
| Non-current financial liabilities |
16,700,000
GBP
|
15,700,000
GBP
|
— |
| Categories of current financial liabilities [abstract] | |||
| Current financial liabilities |
15,100,000
GBP
|
105,500,000
GBP
|
— |
| Miscellaneous non-current liabilities [abstract] | |||
| Non-current net defined benefit liability |
21,800,000
GBP
|
23,300,000
GBP
|
— |
| Miscellaneous current liabilities [abstract] | |||
| Current derivative financial liabilities |
2,500,000
GBP
|
5,100,000
GBP
|
— |
| Issued capital [abstract] | |||
| Issued capital |
9,300,000
GBP
|
9,300,000
GBP
|
— |
| Retained earnings [abstract] | |||
| Retained earnings |
762,300,000
GBP
|
635,500,000
GBP
|
— |
| Miscellaneous equity [abstract] | |||
| Capital redemption reserve |
75,000,000
GBP
|
75,000,000
GBP
|
— |
| Net assets (liabilities) [abstract] | |||
| Assets |
2,713,900,000
GBP
|
2,401,900,000
GBP
|
— |
| Liabilities |
1,969,100,000
GBP
|
1,771,000,000
GBP
|
— |
| Assets (liabilities) |
744,800,000
GBP
|
630,900,000
GBP
|
— |
| Net current assets (liabilities) [abstract] | |||
| Current assets |
2,165,200,000
GBP
|
1,856,800,000
GBP
|
— |
| Current liabilities |
1,783,700,000
GBP
|
1,586,200,000
GBP
|
— |
| Assets less current liabilities [abstract] |