Available for Sale Securities - Investments Pledged as Collateral to Secure Public Deposits and Securities Sold Under Agreements to Repurchase (Details) - USD ($) $ in Millions	Dec. 31, 2022	Jun. 30, 2022
Pledged as collateral \| Public deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 183.6	$ 198.3
Mortgage-Backed Securities \| Pledged as collateral \| Public deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	120.9	126.3
Collateralized Mortgage Obligations
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	24.9
Collateralized Mortgage Obligations \| Pledged as collateral \| Public deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	24.9	27.3
US States and Political Subdivisions Debt Securities [Member]
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	35.9
US States and Political Subdivisions Debt Securities [Member] \| Pledged as collateral \| Public deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	35.9	42.3
Other Debt Obligations [Member] \| Pledged as collateral \| Public deposits
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 2.0	$ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(m)(1)(ii)(A)(i))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

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+ References

No definition available.

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- Definition

The aggregate fair value as of the balance sheet date of financial instruments and other positions owned by the entity including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. Includes both pledged and unpledged holdings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 940
-SubTopic 320
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=35711157&loc=d3e42546-110969

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