Financial Liabilities - Borrowings - Summary of Maturity of the Group's Finance Lease Obligations (Detail) - GBP (£) £ in Millions	Dec. 31, 2017	Dec. 31, 2016
Disclosure of detailed information about borrowings [line items]
Future finance charges on finance leases	£ 0	£ 0
Present value of finance lease liabilities	8	9
In less than one year [member]
Disclosure of detailed information about borrowings [line items]
Finance lease liabilities - minimum lease payments	4	5
Later than one year and not later than two years [member]
Disclosure of detailed information about borrowings [line items]
Finance lease liabilities - minimum lease payments	3	3
Later than two years and not later than three years [member]
Disclosure of detailed information about borrowings [line items]
Finance lease liabilities - minimum lease payments	£ 1	£ 1

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

No definition available.

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- Definition

The amount representing the difference between the future minimum finance lease payments and their present value. Minimum lease payments are payments over the lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with: (a) for a lessee, any amounts guaranteed by the lessee or by a party related to the lessee; or (b) for a lessor, any residual value guaranteed to the lessor by: (i) the lessee; (ii) a party related to the lessee; or (iii) a third party unrelated to the lessor that is financially capable of discharging the obligations under the guarantee.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2019-01-01
-Name IAS
-Number 17
-IssueDate 2017-01-01
-Paragraph 31
-Subparagraph b
-URI http://eifrs.ifrs.org/eifrs/XBRL?type=IAS&num=17&date=2017-03-02&anchor=para_31_b&doctype=Standard&book=B
-URIDate 2017-03-09

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- Definition

The amount of payments over the finance lease term that the lessee is or can be required to make, excluding contingent rent, costs for services and taxes to be paid by, and reimbursed to, the lessor, together with any amounts guaranteed by the lessee or by a party related to the lessee.

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- Definition

The present value of minimum finance lease payments payable. [Refer: Minimum finance lease payments payable]

+ References

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