Outstanding Loans and Leases and Allowance for Credit Losses - Credit Quality Indicators, Narrative (Details) - USD ($) $ in Billions	Dec. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Commercial reservable criticized utilized exposure, amount	$ 38.7	$ 11.5
Commercial reservable criticized utilized exposure, percent	7.31%	2.09%

Commercial Reservable Criticized Utilized Exposure, Amount

No definition available.

Name:	bac_CommercialReservableCriticizedUtilizedExposureAmount
Namespace Prefix:	bac_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant