XML 88 R73.htm IDEA: XBRL DOCUMENT
v3.25.1

Note 4 - Loans Receivable and Allowance for Credit Losses on Loans - Schedule of Amortized Cost of Nonaccrual Loans (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Financing Receivable, Nonaccrual, No Allowance |  | $ 5,682 | $ 1,357
Financing Receivable, Nonaccrual, With Allowance |  | 7,919 | 9,595
Financing Receivable, Nonaccrual | [1] | 13,601 | 10,952
Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 3,196 | 1,357
Financing Receivable, Nonaccrual, With Allowance |  | 4,979 | 4,699
Financing Receivable, Nonaccrual | [1] | 8,175 | 6,056
Real Estate Portfolio Segment [Member] | Commercial Real Estate [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 2,771 | 1,088
Financing Receivable, Nonaccrual, With Allowance |  | 0 | 0
Financing Receivable, Nonaccrual |  | 2,771 | 1,088
Real Estate Portfolio Segment [Member] | Construction Loans [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 0 | 0
Financing Receivable, Nonaccrual, With Allowance |  | 4,979 | 4,699
Financing Receivable, Nonaccrual | [1] | 4,979 | 4,699
Real Estate Portfolio Segment [Member] | Home Equity Loan [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 261 | 173
Financing Receivable, Nonaccrual, With Allowance |  | 0 | 0
Financing Receivable, Nonaccrual | [1] | 261 | 173
Real Estate Portfolio Segment [Member] | One-to-four Family Loan [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 164 | 96
Financing Receivable, Nonaccrual, With Allowance |  | 0 | 0
Financing Receivable, Nonaccrual | [1] | 164 | 96
Consumer Portfolio Segment [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  |  | 0
Financing Receivable, Nonaccrual, With Allowance |  | 1,980 | 2,213
Financing Receivable, Nonaccrual | [1] | 1,980 | 2,213
Consumer Portfolio Segment [Member] | Indirect Home Improvement Loan [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 0 | 0
Financing Receivable, Nonaccrual, With Allowance |  | 1,677 | 1,863
Financing Receivable, Nonaccrual | [1] | 1,677 | 1,863
Consumer Portfolio Segment [Member] | Marine Loans [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 0 | 0
Financing Receivable, Nonaccrual, With Allowance |  | 289 | 342
Financing Receivable, Nonaccrual | [1] | 289 | 342
Consumer Portfolio Segment [Member] | Other Consumer Loan [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 0 | 0
Financing Receivable, Nonaccrual, With Allowance |  | 14 | 8
Financing Receivable, Nonaccrual | [1] | 14 | 8
Commercial Business Portfolio Segment [Member] |  |  |
Financing Receivable, Nonaccrual | [1] | 3,446 | 2,683
Commercial Business Portfolio Segment [Member] | Commercial And Industrial [Member] |  |  |
Financing Receivable, Nonaccrual, No Allowance |  | 2,486 | 0
Financing Receivable, Nonaccrual, With Allowance |  | 960 | 2,683
Financing Receivable, Nonaccrual | [1] | $ 3,446 | $ 2,683
[1] | Includes loans less than 90 days past due as applicable.

X
- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with allowance for credit loss. Excludes net investment in lease. + References No definition available. + Details
Name: | fsbw_FinancingReceivableExcludingAccruedInterestNonaccrualWithAllowance
Namespace Prefix: | fsbw_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-16 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrual
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortized cost excluding accrued interest, of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 16 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-16 + Details
Name: | us-gaap_FinancingReceivableExcludingAccruedInterestNonaccrualNoAllowance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

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

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

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

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=fsbw_OnetofourFamilyLoanMember
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: |

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

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

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

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

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