Minimum cash and minimum capital - Additional Information (Detail)	12 Months Ended
Dec. 31, 2022
Minimum Capital [Abstract]
Item Of Minimum Capital Requirement For Credit Risk	8

The amount of minimum capital requirement for credit risk, percent of the sum of credit-risk-weighted asset transactions without delivery against payment.

No definition available.

Name:	bbar_ItemOfMinimumCapitalRequirementForCreditRisk
Namespace Prefix:	bbar_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration