Loans Receivable Held for Investment, Average of Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Average recorded investment	$ 4,361	$ 5,124	$ 4,512	$ 5,158
Cash basis interest income recognized	72	87	147	336
Foregone interest income	19	22	38	45
30 - 89 Days Past Due [Member]
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Loans delinquent amount	1,900		1,900
Greater than 90 Days Past Due [Member]
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Loans delinquent amount	0		0
Real Estate [Member] \| Single Family [Member]
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Average recorded investment	316	597	426	599
Cash basis interest income recognized	4	7	10	14
Real Estate [Member] \| Multi-Family [Member]
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Average recorded investment	292	308	294	309
Cash basis interest income recognized	5	5	10	11
Real Estate [Member] \| Church [Member]
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Average recorded investment	3,742	4,160	3,766	4,190
Cash basis interest income recognized	63	74	126	309
Commercial - Other [Member]
Loans Individually Evaluated for Impairment by Loan Type and Related Interest Income [Abstract]
Average recorded investment	11	59	26	60
Cash basis interest income recognized	$ 0	$ 1	$ 1	$ 2

No definition available.

Name:	byfc_LoansIndividuallyEvaluatedForImpairmentByLoanTypeAndRelatedInterestIncomeAbstract
Namespace Prefix:	byfc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

This is the principal amount of loans (across all types of loans) that are overdue in payment by a set number of days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (e)(4)
-URI http://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

+ Details

Name:	us-gaap_DelinquentAmountAtEndOfPeriodOnLoansManagedAndSecuritized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5258-111524

+ Details

Name:	us-gaap_ImpairedFinancingReceivableAverageRecordedInvestment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of interest income recognized on a cash-basis method of accounting that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

+ Details

Name:	us-gaap_ImpairedFinancingReceivableInterestIncomeCashBasisMethod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

+ Details

Name:	us-gaap_LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=byfc_FinancingReceivables30To89DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivablesEqualToGreaterThan90DaysPastDueMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=byfc_SingleFamilyLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=byfc_MultifamilyLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=byfc_ChurchLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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