Borrowings (Details) $ in Millions	9 Months Ended	12 Months Ended
Mar. 31, 2024 USD ($) item	Jun. 30, 2023 USD ($)
Federal Home Loan Bank, Advances [Line Items]
FHLB number of regional banks \| item	11
Maximum borrowing capacity with FHLB	$ 280.8	$ 295.0
Fixed rate short-term borrowings	65.0	34.0
Loans pledged as collateral	406.5	427.2
Investments	3.5	2.3
Collateral pledged in support of federal reserve bank advances outstanding	9.9	10.2
Maximum advances or credit lines available from the Federal Reserve Bank	4.1	3.7
Balance for the overnight line of credit	0.0	0.0
Atlantic Community Bankers Bank
Federal Home Loan Bank, Advances [Line Items]
Available credit to purchase federal funds	$ 10.0	$ 10.0

Amount of Federal Home Loan Bank (FHLBank) advances to member financial institutions.

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- Definition

The calculated average balance outstanding for the year for all Federal Home Loan Bank advances as of the Balance Sheet date.

+ References

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- Definition

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.13(3)(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480876/942-470-45-1

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22 (b))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480876/942-470-45-1

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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480848/942-470-50-3

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- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

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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.

+ References

No definition available.

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Amount of borrowings as of the balance sheet date from the Federal Reserve Bank.

+ References

No definition available.

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- Definition

Represents the information pertaining to F H L B number of regional banks.

+ References

No definition available.

+ Details

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- Definition

Amount of the collateral pledged in support of federal reserve bank advances outstanding.

+ References

No definition available.

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- Definition

Amount of maximum advances or credit lines available from the Federal Reserve Bank.

+ References

No definition available.

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