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
-Topic 326
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-Name Accounting Standards Codification
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-Topic 326
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-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

+ Details

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

- Details

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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 ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
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	$ 13,000,000		$ 13,000,000		$ 19,000,000
Amount of loss reserve account	4,700,000		4,700,000		4,900,000
Pacific Enterprise Bancorp
ALLOWANCE FOR CREDIT LOSSES FOR LOANS
Total loan enrolled under the program	3,800,000		3,800,000		9,300,000
Amount of loss reserve account	2,400,000		2,400,000		$ 4,900,000
Amount of loan originated under the program	$ 530,000	$ 5,500,000	$ 825,000	$ 8,900,000