Trade and Other Receivables - Additional Information (Detail) - GBP (£) £ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Disclosure of other provisions [line items]
Impairment charges on accrued income assets	£ 0	£ 0
Trade and other receivables	1,257	1,118
Disposal groups classified as held for sale [member]
Disclosure of other provisions [line items]
Trade and other receivables	£ 0	£ 6

Line items represent concepts included in a table. These concepts are used to disclose reportable information associated with members defined in one or many axes of the table.

No definition available.

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- Definition

The amount of impairment loss on receivables or contract assets arising from contracts with customers. [Refer: Contract assets; Impairment loss; Receivables from contracts with customers]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 15
-IssueDate 2021-01-01
-Paragraph 113
-Subparagraph b
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-URIDate 2021-03-24

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- Definition

The amount of current trade receivables and current other receivables. [Refer: Current trade receivables; Other current receivables]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2021-01-01
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