Loans and Allowance for Credit Losses on Loans, Allowance for Credit Losses on Loans (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Jun. 30, 2024
Allowance for Credit Loss [Abstract]
Threshold principal amount of collateral dependent loans evaluated individually	$ 250
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period	19,244	$ 21,212	$ 21,212
Charge-offs	(145)	(129)
Recoveries	31	36
Provision	651	462
Balance, end of period	$ 19,781	20,249	19,244
Cumulative Effect Adjustment for ASU Implementation [Member] \| Adoption of ASU No. 2016-13 [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period		(1,332)	(1,332)
Smaller Business Loans [Member] \| Uncollateralized [Member]
Allowance for Credit Loss [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days
Residential Portfolio [Member] \| Residential Real Estate [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period	$ 4,237	2,794	2,794
Charge-offs	(44)	0	0
Recoveries	2	0
Provision	280	317
Balance, end of period	4,475	4,293	4,237
Residential Portfolio [Member] \| Residential Real Estate [Member] \| Cumulative Effect Adjustment for ASU Implementation [Member] \| Adoption of ASU No. 2016-13 [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period		1,182	1,182
Commercial Real Estate Portfolio [Member] \| Real Estate [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period	12,218	14,839	14,839
Charge-offs	(5)	0	0
Recoveries	1	1
Provision	434	405
Balance, end of period	$ 12,648	12,356	12,218
Commercial Real Estate Portfolio [Member] \| Real Estate [Member] \| Cumulative Effect Adjustment for ASU Implementation [Member] \| Adoption of ASU No. 2016-13 [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period		(2,889)	(2,889)
Consumer Portfolio [Member] \| Uncollateralized [Member]
Allowance for Credit Loss [Abstract]
Threshold period to charge off loans against allowance for loan losses	90 days
Threshold period to charge off overdrawn deposit accounts against allowance for loan losses	60 days
Consumer Portfolio [Member] \| Home Equity [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period	$ 212	46	46
Charge-offs	(13)	0	0
Recoveries	0	0
Provision	33	25
Balance, end of period	232	188	212
Consumer Portfolio [Member] \| Home Equity [Member] \| Cumulative Effect Adjustment for ASU Implementation [Member] \| Adoption of ASU No. 2016-13 [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period		117	117
Consumer Portfolio [Member] \| Consumer [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period	500	332	332
Charge-offs	(77)	(122)	(481)
Recoveries	19	26
Provision	12	117
Balance, end of period	454	490	500
Consumer Portfolio [Member] \| Consumer [Member] \| Cumulative Effect Adjustment for ASU Implementation [Member] \| Adoption of ASU No. 2016-13 [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period		137	137
Commercial Portfolio [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period	2,077	3,201	3,201
Charge-offs	(6)	(7)	(1,152)
Recoveries	9	9
Provision	(108)	(402)
Balance, end of period	$ 1,972	2,922	2,077
Commercial Portfolio [Member] \| Cumulative Effect Adjustment for ASU Implementation [Member] \| Adoption of ASU No. 2016-13 [Member]
Activity and Allocation of Allowance for Credit Losses on Loans by Segment [Roll Forward]
Balance, beginning of period		$ 121	$ 121

The threshold principal amount of collateral dependent loans evaluated individually.

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- Definition

Threshold period for overdrawn financing receivable to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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- Definition

Amount of increase in allowance for credit loss on financing receivable from recovery.

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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.

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

+ References

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- Definition

Threshold period for when financing receivable is considered past due to write off as uncollectible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Amount of credit loss expense (reversal of expense) for financing receivable.

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