Name:	bbplc_Leases
Namespace Prefix:	bbplc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

The number of leases held by the entity.

No definition available.

Name:	bbplc_NumberOfLeases
Namespace Prefix:	bbplc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The number of leases with variable lease payment terms based on market based pricing adjustments.

No definition available.

Name:	bbplc_NumberOfLeasesWithVariableLeasePaymentTerms
Namespace Prefix:	bbplc_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

The amount of the expense relating to variable lease payments not included in the measurement of lease liabilities. Variable lease payments are the portion of payments made by a lessee to a lessor for the right to use an underlying asset during the lease term that varies because of changes in facts or circumstances occurring after the commencement date, other than the passage of time. [Refer: Lease liabilities]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2022-03-24
-Paragraph 53
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2022-en-r&anchor=para_53_e&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_ExpenseRelatingToVariableLeasePaymentsNotIncludedInMeasurementOfLeaseLiabilities
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The gains (losses) arising from sale and leaseback transactions.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 16
-IssueDate 2022-03-24
-Paragraph 53
-Subparagraph i
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=16&code=ifrs-tx-2022-en-r&anchor=para_53_i&doctype=Standard
-URIDate 2022-03-24