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Loans - Payment Status (Amortized Cost Basis) (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | $ 35,489 | $ 14,529
30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 1,854 | 2,113
90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 3,103 | 2,122
Residential real estate | Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 8,897 | 1,660
Residential real estate | 30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 110 | 1,495
Residential real estate | 90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 206 | 115
Commercial and industrial | Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 26,582 | 12,865
Commercial and industrial | 30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 1,744 | 618
Commercial and industrial | 90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 2,897 | 2,007
Consumer | Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 10 | 4
Consumer | 30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 0 | 0
Consumer | 90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 0 | 0
Commercial real estate | Residential real estate | Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 2,516 | 272
Commercial real estate | Residential real estate | 30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 110 | 10
Commercial real estate | Residential real estate | 90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 0 | 0
Construction/land/land development | Residential real estate | Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 4,138 | 452
Construction/land/land development | Residential real estate | 30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 0 | 0
Construction/land/land development | Residential real estate | 90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 206 | 0
Residential real estate | Residential real estate | Current |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 2,243 | 936
Residential real estate | Residential real estate | 30-89 Days Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | 0 | 1,485
Residential real estate | Residential real estate | 90 Days or More Past Due |  |
Financing Receivable, Past Due [Line Items] |  |
Total LHFI | $ 0 | $ 115

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