Available for Sale Securities - Investments Pledged as Collateral to Secure Public Deposits and Securities Sold Under Agreements to Repurchase (Details) - Public deposits - USD ($) $ in Millions	Jun. 30, 2023	Jun. 30, 2022
Pledged as collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 253.9	$ 198.3
Asset backed securities
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	129.2	126.3
Asset backed securities \| Pledged as collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral		27.3
Collateralized Mortgage Obligations
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	94.8
US States and Political Subdivisions Debt Securities [Member] \| Pledged as collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	26.5	42.3
Other Debt Obligations [Member] \| Pledged as collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Carrying value of investment and MBS pledged as collateral to secure public deposits and securities sold under agreements to repurchase	$ 3.4	$ 2.4

Carrying amount of assets sold under agreements to repurchase when the carrying amount (or market value, if higher than the carrying amount) of securities or other assets sold under repurchase agreements exceeds 10 percent of total assets.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480678/235-10-S99-1

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481444/860-30-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6-04(11))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479617/946-210-S99-1

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481961/940-320-45-2

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