XML 45 R35.htm IDEA: XBRL DOCUMENT
v3.25.3

Note 4 - Loans - Schedule of Past Due Financing Receivables (Details) - USD ($) | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Total loans | $ 671,771,935 | $ 714,337,185
Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 89,332 | 119,309
Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 1,948,168 | 1,607,835
Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 19,756,503 | 12,612,035
Financial Asset, Past Due [Member] |  |
Total loans | 21,794,003 | 14,339,179
Financial Asset, Not Past Due [Member] |  |
Total loans | 649,977,932 | 699,998,006
Residential Portfolio Segment [Member] | Real Estate Loan [Member] |  |
Total loans | 449,596,294 | 472,747,542
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 69,992 | 119,309
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 88,237 | 1,607,835
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 1,801,822 | 513,297
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, Past Due [Member] |  |
Total loans | 1,960,051 | 2,240,441
Residential Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, Not Past Due [Member] |  |
Total loans | 447,636,243 | 470,507,101
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member] |  |
Total loans | 122,811,801 | 118,008,866
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 0 | 0
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 1,859,931 | 0
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 7,060,968 | 1,205,025
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, Past Due [Member] |  |
Total loans | 8,920,899 | 1,205,025
Commercial Real Estate Portfolio Segment [Member] | Real Estate Loan [Member] | Financial Asset, Not Past Due [Member] |  |
Total loans | 113,890,902 | 116,803,841
Multi-Family Real Estate [Member] | Real Estate Loan [Member] |  |
Total loans | 70,364,169 | 74,152,418
Multi-Family Real Estate [Member] | Real Estate Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 0 | 0
Multi-Family Real Estate [Member] | Real Estate Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 0 | 0
Multi-Family Real Estate [Member] | Real Estate Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 0 | 0
Multi-Family Real Estate [Member] | Real Estate Loan [Member] | Financial Asset, Past Due [Member] |  |
Total loans | 0 | 0
Multi-Family Real Estate [Member] | Real Estate Loan [Member] | Financial Asset, Not Past Due [Member] |  |
Total loans | 70,364,169 | 74,152,418
Construction Loans [Member] | Real Estate Loan [Member] |  |
Total loans | 25,231,859 | 43,183,657
Construction Loans [Member] | Real Estate Loan [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 0 | 0
Construction Loans [Member] | Real Estate Loan [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 0 | 0
Construction Loans [Member] | Real Estate Loan [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 10,893,713 | 10,893,713
Construction Loans [Member] | Real Estate Loan [Member] | Financial Asset, Past Due [Member] |  |
Total loans | 10,893,713 | 10,893,713
Construction Loans [Member] | Real Estate Loan [Member] | Financial Asset, Not Past Due [Member] |  |
Total loans | 14,338,146 | 32,289,944
Commercial and Industrial [Member] |  |
Total loans | 3,703,476 | 6,163,747
Commercial and Industrial [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 19,340 | 0
Commercial and Industrial [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 0 | 0
Commercial and Industrial [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 0 | 0
Commercial and Industrial [Member] | Financial Asset, Past Due [Member] |  |
Total loans | 19,340 | 0
Commercial and Industrial [Member] | Financial Asset, Not Past Due [Member] |  |
Total loans | 3,684,136 | 6,163,747
Commercial and Industrial [Member] | Real Estate Loan [Member] |  |
Total loans | 3,703,476 | 6,163,747
Consumer Portfolio Segment [Member] |  |
Total loans | 64,336 | 80,955
Consumer Portfolio Segment [Member] | Financial Asset, 30 to 59 Days Past Due [Member] |  |
Total loans | 0 | 0
Consumer Portfolio Segment [Member] | Financial Asset, 60 to 89 Days Past Due [Member] |  |
Total loans | 0 | 0
Consumer Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member] |  |
Total loans | 0 | 0
Consumer Portfolio Segment [Member] | Financial Asset, Past Due [Member] |  |
Total loans | 0 | 0
Consumer Portfolio Segment [Member] | Financial Asset, Not Past Due [Member] |  |
Total loans | $ 64,336 | $ 80,955

X
- Definition Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 3B -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-5 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestBeforeAllowanceForCreditLoss
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables30To59DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancingReceivables60To89DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_RealEstateLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=bsbk_MultifamilyRealEstateMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConstructionLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=bsbk_CommercialAndIndustrialMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |