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The amount of cash collateral and settlement balance assets, expressed as a percentage.

No definition available.

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The amount of cash and bank balances held at central banks, expressed as a percentage.

No definition available.

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The amount of financial assets classified as derivative instruments, expressed as a percentage.

No definition available.

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The amount of financial assets at fair value through profit or loss classified as held for trading, expressed as a percentage. A financial asset is classified as held for trading if: (a) it is acquired principally for the purpose of selling it in the near term; (b) on initial recognition it is part of a portfolio of identified financial instruments that are managed together and for which there is evidence of a recent actual pattern of short-term profit-taking; or (c) it is a derivative (except for a derivative that is a financial guarantee contract or a designated and effective hedging instrument). [Refer: At fair value [member]; Financial assets at fair value through profit or loss]

No definition available.

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The amount of financial assets (expressed as a percentage) that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

No definition available.

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The amount (expressed as a percentage) of financial assets that are measured at fair value through other comprehensive income. A financial asset shall be measured at fair value through other comprehensive income if both of the following conditions are met: (a) the financial asset is held within a business model whose objective is achieved by both collecting contractual cash flows and selling financial assets and (b) the contractual terms of the financial asset give rise on specified dates to cash flows that are solely payments of principal and interest on the principal amount outstanding. [Refer: At fair value [member]; Financial assets]

No definition available.

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The amount loans and advances at amortised cost, expressed as a percentage.

No definition available.

Name:	bbplc_LoansAndReceivablesPercentage
Namespace Prefix:	bbplc_
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Balance Type:	na
Period Type:	instant

- References

No definition available.

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- References

No definition available.

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The amount of financial assets that the entity does not separately disclose in the same statement or note, expressed as a percentage.

No definition available.

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The amount of instruments purchased for resale in reverse repurchase agreements and cash collateral on securities borrowed, expressed as a percentage.

No definition available.

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The amount of a present economic resource controlled by the entity as a result of past events. Economic resource is a right that has the potential to produce economic benefits.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2022-03-24
-Paragraph 28
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2022-en-r&anchor=para_28_c&doctype=Standard
-URIDate 2022-03-24

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2022-en-r&anchor=para_93_b&doctype=Standard
-URIDate 2022-03-24

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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-Paragraph 93
-Subparagraph e
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=13&code=ifrs-tx-2022-en-r&anchor=para_93_e&doctype=Standard
-URIDate 2022-03-24

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 8
-IssueDate 2022-03-24
-Paragraph 23
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=8&code=ifrs-tx-2022-en-r&anchor=para_23&doctype=Standard
-URIDate 2022-03-24

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_55&doctype=Standard
-URIDate 2022-03-24

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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of bank acceptances recognised as assets.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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The amount of cash and bank balances held at central banks.

Name:	ifrs-full_CashAndBankBalancesAtCentralBanks
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of financial assets classified as derivative instruments. [Refer: Financial assets; Derivatives [member]]

Name:	ifrs-full_DerivativeFinancialAssets
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Data Type:	xbrli:monetaryItemType
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The amount of financial assets that are measured at fair value and for which gains (losses) are recognised in profit or loss. A financial asset shall be measured at fair value through profit or loss unless it is measured at amortised cost or at fair value through other comprehensive income. A gain (loss) on a financial asset measured at fair value shall be recognised in profit or loss unless it is part of a hedging relationship, it is an investment in an equity instrument for which the entity has elected to present gains and losses in other comprehensive income or it is a financial asset measured at fair value through other comprehensive income. [Refer: At fair value [member]; Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 8
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_8_a&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_FinancialAssetsAtFairValueThroughProfitOrLoss
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

The amount of financial assets at fair value through profit or loss classified as held for trading. A financial asset is classified as held for trading if: (a) it is acquired principally for the purpose of selling it in the near term; (b) on initial recognition it is part of a portfolio of identified financial instruments that are managed together and for which there is evidence of a recent actual pattern of short-term profit-taking; or (c) it is a derivative (except for a derivative that is a financial guarantee contract or a designated and effective hedging instrument). [Refer: At fair value [member]; Financial assets at fair value through profit or loss]

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 55
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_55&doctype=Standard
-URIDate 2022-03-24

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 8
-Subparagraph a
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_8_a&doctype=Standard&book=b
-URIDate 2022-03-24

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of financial assets that are measured at fair value through other comprehensive income. A financial asset shall be measured at fair value through other comprehensive income if both of the following conditions are met: (a) the financial asset is held within a business model whose objective is achieved by both collecting contractual cash flows and selling financial assets and (b) the contractual terms of the financial asset give rise on specified dates to cash flows that are solely payments of principal and interest on the principal amount outstanding. [Refer: At fair value [member]; Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 8
-Subparagraph h
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2022-en-r&anchor=para_8_h&doctype=Standard
-URIDate 2022-03-24

Name:	ifrs-full_FinancialAssetsMeasuredAtFairValueThroughOtherComprehensiveIncome
Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
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The amount of non-derivative financial assets with fixed or determinable payments that are not quoted in an active market, other than: (a) those that the entity intends to sell immediately or in the near term, which shall be classified as held for trading, and those that the entity, upon initial recognition, designates as at fair value through profit or loss; (b) those that the entity, upon initial recognition, designates as available for sale; or (c) those for which the holder may not recover substantially all of its initial investment, other than because of credit deterioration, which shall be classified as available for sale. An interest acquired in a pool of assets that are not loans or receivables (for example, an interest in a mutual fund or a similar fund) is not a loan or receivable. [Refer: Derivative financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Note Expiry date 2023-01-01
-Name IFRS
-Number 7
-IssueDate 2022-03-24
-Paragraph 8
-Subparagraph c
-URI https://taxonomy.ifrs.org/xifrs-link?type=IFRS&num=7&code=ifrs-tx-2017-en-b&anchor=para_8_c&doctype=Standard&book=b
-URIDate 2022-03-24

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Namespace Prefix:	ifrs-full_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of financial assets that the entity does not separately disclose in the same statement or note. [Refer: Financial assets]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IAS
-Number 1
-IssueDate 2022-03-24
-Paragraph 54
-Subparagraph d
-URI https://taxonomy.ifrs.org/xifrs-link?type=IAS&num=1&code=ifrs-tx-2022-en-r&anchor=para_54_d&doctype=Standard
-URIDate 2022-03-24

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The amount of instruments purchased for resale in reverse repurchase agreements and cash collateral on securities borrowed. [Refer: Repurchase agreements and cash collateral on securities lent]

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Namespace Prefix:	ifrs-full_
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Period Type:	instant

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Name:	ifrs-full_InternalCreditGradesAxis=ifrs-full_InternalCreditGradesMember
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