Loans and Allowance for Credit Losses - Credit risk profile based on rating and payment activity (Details) - USD ($) $ in Millions	12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Pass
Financing Receivable, Credit Quality Indicator [Line Items]
PCD loans receivable, net of ACL	$ 37.4	$ 23.1
Watch
Financing Receivable, Credit Quality Indicator [Line Items]
PCD loans receivable, net of ACL	12.7	4.7
Special Mention
Financing Receivable, Credit Quality Indicator [Line Items]
PCD loans receivable, net of ACL	0.0	0.0
Substandard
Financing Receivable, Credit Quality Indicator [Line Items]
PCD loans receivable, net of ACL	6.3	1.1
Doubtful
Financing Receivable, Credit Quality Indicator [Line Items]
PCD loans receivable, net of ACL	$ 0.0	$ 0.0