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LOANS AND LEASES - Schedule of Loans Modified, Past Due (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Sep. 30, 2024
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | $ 989 | $ 736
Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 873 | 697
30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 11 | 3
60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 5 | 11
90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 100 | 25
Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 935 | 714
Commercial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 831 | 682
Commercial | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 8 | 2
Commercial | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 2 | 9
Commercial | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 94 | 21
Commercial | Commercial construction |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 23 | 3
Commercial | Commercial construction | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 22 | 3
Commercial | Commercial construction | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Commercial | Commercial construction | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Commercial | Commercial construction | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Commercial | Owner occupied commercial mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 84 | 61
Commercial | Owner occupied commercial mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 74 | 50
Commercial | Owner occupied commercial mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Commercial | Owner occupied commercial mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 9
Commercial | Owner occupied commercial mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 9 | 2
Commercial | Non-owner occupied commercial mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 306 | 173
Commercial | Non-owner occupied commercial mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 241 | 156
Commercial | Non-owner occupied commercial mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 4 | 1
Commercial | Non-owner occupied commercial mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Commercial | Non-owner occupied commercial mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 60 | 16
Commercial | Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 431 | 349
Commercial | Commercial and industrial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 404 | 346
Commercial | Commercial and industrial | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 2 | 1
Commercial | Commercial and industrial | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Commercial | Commercial and industrial | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 24 | 2
Commercial | Investor dependent |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 91 | 128
Commercial | Investor dependent | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 90 | 127
Commercial | Investor dependent | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Commercial | Investor dependent | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Commercial | Investor dependent | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 1
Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 54 | 22
Consumer | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 42 | 15
Consumer | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 1
Consumer | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 2
Consumer | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 6 | 4
Consumer | Residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 47 | 16
Consumer | Residential mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 35 | 9
Consumer | Residential mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 1
Consumer | Residential mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 2
Consumer | Residential mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 6 | 4
Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 7 | 6
Consumer | Revolving mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 7 | 6
Consumer | Revolving mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Consumer | Revolving mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Consumer | Revolving mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | $ 0 | $ 0

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