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Commitment and Contingencies - Schedule of Allowance for Credit Losses for Unfunded Loan Commitments (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |
Beginning ACL | $ 327 | $ 332
Provision for (recapture of) credit losses | 105 | (71)
Ending ACL | 432 | 327
Impact of Adopting CECL (ASU 2016-13) |  |
Off-Balance-Sheet, Credit Loss, Liability [Roll Forward] |  |
Beginning ACL | $ 0 | 66
Ending ACL |  | $ 0

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- Definition Provision for Loan, Lease, and Other Losses, Unfunded Commitment + References No definition available. + Details
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- Definition Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-2 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482454/460-10-45-1 + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Details
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