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
-SubTopic 20
-Name Accounting Standards Codification
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-Publisher FASB
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-Topic 326
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-Topic 326
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-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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-Paragraph 13
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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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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 ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 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	$ 13.0		$ 13.0		$ 19.0
Amount of loss reserve account	3.2		3.2		4.9
Amount of loan originated under the program	2.0	$ 3.3	2.8	$ 12.1
Pacific Enterprise Bancorp
ALLOWANCE FOR CREDIT LOSSES FOR LOANS
Total loan enrolled under the program	3.0		3.0		9.3
Amount of loss reserve account	$ 2.0		$ 2.0		$ 4.9