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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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