Recent Accounting Pronouncements - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Sep. 30, 2023
Debt Securities, Held-to-Maturity, Allowance for Credit Loss [Line Items]
Adjustment to retained earnings, net of deferred tax; - adoption of ASU 2016-13	$ 488	$ 0
Adjustment to opening balance	461
Allowance for Credit Losses ("ACL")	82		$ 0
Allowance for credit losses for unfunded loan commitments	364		332
Financing Receivable, Allowance for Credit Loss, Writeoff	$ 2	$ 0
Impact of Adopting CECL (ASU 2016-13)
Debt Securities, Held-to-Maturity, Allowance for Credit Loss [Line Items]
Allowance for Credit Losses ("ACL")			92
Allowance for credit losses for unfunded loan commitments			$ 65

Adjustment to Retained Earnings, Net Of Deferred Tax, Adoption Of Accounting Standards Update

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- Definition

Debt Securities, Held-to-Maturity, Allowance For Credit Loss, Excluding Accrued Interest, Adjustment

+ References

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Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of writeoff of financing receivable, charged against allowance for credit loss.

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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.

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