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LOANS AND LEASES - Schedule of Loans Modified, Past Due (Details) - USD ($) $ in Millions | Mar. 31, 2025 | Mar. 31, 2024
--- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | $ 750 | $ 696
Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 696 | 611
30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 20 | 49
60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 2
90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 31 | 34
Commercial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 513 | 501
Commercial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 470 | 451
Commercial | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 16 | 46
Commercial | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 2 | 2
Commercial | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 25 | 2
Commercial | Commercial construction |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 25 | 4
Commercial | Commercial construction | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 25 | 4
Commercial | Commercial construction | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 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 | 65 | 29
Commercial | Owner occupied commercial mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 61 | 26
Commercial | Owner occupied commercial mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 2
Commercial | Owner occupied commercial mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Commercial | Owner occupied commercial mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 1
Commercial | Non-owner occupied commercial mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 236 | 353
Commercial | Non-owner occupied commercial mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 204 | 314
Commercial | Non-owner occupied commercial mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 9 | 39
Commercial | Non-owner occupied commercial mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
Commercial | Non-owner occupied commercial mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 23 | 0
Commercial | Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 187 | 115
Commercial | Commercial and industrial | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 180 | 107
Commercial | Commercial and industrial | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 4 | 5
Commercial | Commercial and industrial | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 2
Commercial | Commercial and industrial | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 2 | 1
Consumer |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 25 | 21
Consumer | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 20 | 19
Consumer | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 1
Consumer | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Consumer | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 1
Consumer | Residential mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 17 | 17
Consumer | Residential mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 12 | 15
Consumer | Residential mortgage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 1
Consumer | Residential mortgage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 1 | 0
Consumer | Residential mortgage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 1
Consumer | Revolving mortgage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 8 | 4
Consumer | Revolving mortgage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 8 | 4
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
SVB |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 212 | 174
SVB | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 206 | 141
SVB | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 2
SVB | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 31
SVB | Investor dependent - early stage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 25 | 27
SVB | Investor dependent - early stage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 22 | 22
SVB | Investor dependent - early stage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 3 | 2
SVB | Investor dependent - early stage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | Investor dependent - early stage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 3
SVB | Investor dependent - growth stage |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 41 | 63
SVB | Investor dependent - growth stage | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 41 | 63
SVB | Investor dependent - growth stage | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | Investor dependent - growth stage | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | Investor dependent - growth stage | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | Innovation C&I and cash flow dependent |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 146 | 84
SVB | Innovation C&I and cash flow dependent | Current |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 143 | 56
SVB | Innovation C&I and cash flow dependent | 30-59 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | Innovation C&I and cash flow dependent | 60-89 Days Past Due |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | 0 | 0
SVB | Innovation C&I and cash flow dependent | 90 Days or Greater |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Total loans and leases | $ 3 | $ 28

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