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Organization and Summary of Significant Accounting Policies - Cash and Cash Equivalents (Details) - USD ($) $ in Millions	3 Months Ended
	Sep. 30, 2025	Jun. 30, 2025
Cash and Cash Equivalents [Line Items]
Securities purchased under agreements to resell	$ 25.3	$ 25.2
Term of interest bearing deposits	3 years
Interest-bearing deposits in other depository institutions
Cash and Cash Equivalents [Line Items]
Cash	$ 76.7	136.9
Deposits are held in various commercial banks
Cash and Cash Equivalents [Line Items]
Cash	$ 1.9	$ 1.8

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