It represents the amount of borrowed or originated under CalCAP loan program.

No definition available.

Name:	bcml_AmountOfLoanBorrowedUnderCalcapProgram
Namespace Prefix:	bcml_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

It represents the amount of loss reserve account under CalCAP loan program.

+ References

No definition available.

+ Details

Name:	bcml_AmountOfLossReserveAccount
Namespace Prefix:	bcml_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

It represents the amount of total loan enrolled in CalCAP loan program.

+ References

No definition available.

+ Details

Name:	bcml_AmountOfTotalLoanEnrolled
Namespace Prefix:	bcml_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Percentage of immediate coverage of loss under CalCAP loan program.

+ References

No definition available.

+ Details

Name:	bcml_ImmediateCoverageOfLossUnderCalcapLoanProgramPercentage
Namespace Prefix:	bcml_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=bcml_CaliforniaPollutionControlFinancingAuthorityLoanProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=bcml_PacificEnterpriseBancorpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=bcml_PacificEnterpriseBancorpMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

ALLOWANCE FOR CREDIT LOSSES FOR LOANS - PEB Acquisition CalCAP loan program (Details) - CalCAP Loan program - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
ALLOWANCE FOR CREDIT LOSSES FOR LOANS
Immediate loss coverage percentage (%)	100.00%		100.00%
Pacific Enterprise Bancorp
ALLOWANCE FOR CREDIT LOSSES FOR LOANS
Total loan enrolled under the program	$ 21.7		$ 21.7		$ 17.3
Amount of loss reserve account	4.7		4.7		3.8
Amount of loan originated under the program	3.3	$ 3.9	12.1	$ 8.4
Pacific Enterprise Bancorp
ALLOWANCE FOR CREDIT LOSSES FOR LOANS
Total loan enrolled under the program	10.5		10.5		17.7
Amount of loss reserve account	$ 7.0		$ 7.0		$ 10.4