Financial assets at fair value through other comprehensive income - Debt securities FVOCI (Detail) - ARS ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Debt securities held fvoci [Abstract]
BCRA Liquidity Bills	$ 468,895,259	$ 209,779,172
Government securities	125,832,474	103,965,304
Financial assets pledged as collateral	16,699,438	8,988,656
Private securities - Corporate bonds	3,722,935	2,648,245
BCRA Internal Bills	2,125,540
TOTAL	$ 617,275,646	$ 325,381,377

The amount of Central Bank of the Argentine Republic bills pledged as collateral held by the entity.

No definition available.

Name:	bbar_BcraBillsPledgedAsCollateralFvoci
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Period Type:	instant

The amount of Central Bank of the Argentine Republic liquidity bills pledged as collateral held by the entity.

No definition available.

Name:	bbar_BcraLiquidityBillsFvoci
Namespace Prefix:	bbar_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of instruments of debt securities held by the entity at fair value through other comprehensive income.

No definition available.

Name:	bbar_DebtSecuritiesHeldFVOCI
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Data Type:	xbrli:monetaryItemType
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Debt securities held fvoci abstract

No definition available.

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Financial asset pledged as collateral for liabilities or contingent liabilities.

No definition available.

Name:	bbar_FinancialAssetPledgedAsCollateralForLiabilitiesOrContingentLiabilities
Namespace Prefix:	bbar_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of government securities held by the entity.

No definition available.

Name:	bbar_GovernmentSecuritiesFvoci
Namespace Prefix:	bbar_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

The amount of debt investment securities by the entity that were issued by a corporate entity.

No definition available.

Name:	bbar_PrivateSecuritiesCorporateBondsFvoci
Namespace Prefix:	bbar_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant