Available for Sale Securities - Investments Pledged as Collateral to Secure Public Deposits and Securities Sold Under Agreements to Repurchase (Details) - Pledged as collateral - Public deposits - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 253.6	$ 265.5
MBS
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	133.2	137.0
CMOs
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	94.0	103.5
Obligations of states and political subdivisions
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	22.3	20.8
Other securities
Financial Instruments Owned and Pledged as Collateral [Line Items]
Securities pledged as collateral	$ 4.1	$ 4.3