Commitments and Contingencies (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitment To Contribute Capital to CRA Related Pool	$ 94,521	$ 76,900
Reserve for Unfunded Loan Commitments	$ 29,571	$ 91,071	$ 73,071

Commitment To Contribute Capital to CRA Related Pool

No definition available.

Name:	banc_CommitmentToContributeCapitaltoCRARelatedPool
Namespace Prefix:	banc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant