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Allowance for Credit Losses (Narrative) (Details) $ in Thousands	3 Months Ended						6 Months Ended
	Mar. 31, 2028	Mar. 31, 2027	Mar. 31, 2026	Mar. 31, 2025	Jun. 30, 2024 USD ($) risk_code	Jun. 30, 2023 USD ($)	Jun. 30, 2024 USD ($) risk_code	Jun. 30, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Length of time projected by model							10 years
Days Past Due on Leases and Equipment Finance							181 days
Interest Income on Non-Accrual Loans and Leases | $					$ 0	$ 0	$ 0	$ 0
Financing Receivable, Modified, Subsequent Default | $					$ 4,357	$ 0	$ 4,357	$ 0
Moody's Analytics' May 2024 S2
Financing Receivable, Allowance for Credit Loss [Line Items]
Probability economy performs better than scenario							75.00%
Probability economy performs worse than scenario							25.00%
Non homogeneous
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing Receivable, Threshold Period Past Due					90 days		90 days
Pass | Non homogeneous | Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					1		1
Pass | Non homogeneous | Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					9		9
Watch | Non homogeneous | Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					10		10
Watch | Non homogeneous | Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					11		11
Special mention | Non homogeneous
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					12		12
Substandard | Non homogeneous | Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					13		13
Substandard | Non homogeneous | Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					14		14
Doubtful | Non homogeneous
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					15		15
Loss | Non homogeneous
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					16		16
Loss | Non homogeneous | Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Internal risk rating code (number)					16		16
Expected | Moody's Analytics' May 2024 baseline
Financing Receivable, Allowance for Credit Loss [Line Items]
Real GDP Growth	2.20%	1.90%	1.70%	2.50%
Unemployment Rate	4.00%	4.00%	4.10%	4.00%
Fed Funds Rate	2.90%	3.30%	4.30%	5.20%
Expected | Moody's Analytics' May 2024 S2
Financing Receivable, Allowance for Credit Loss [Line Items]
Real GDP Growth	2.70%	2.50%	0.10%	2.00%
Unemployment Rate	4.00%	4.40%	6.10%	4.50%
Fed Funds Rate	2.70%	2.20%	2.80%	5.00%

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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.

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