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LOANS, LEASES, AND ALLOWANCE FOR CREDIT LOSSES (Summary of Nonaccrual Loans) (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | $ 75 | $ 112
Amortized cost basis with allowance | 244 | 185
Nonaccrual loans that are current | 319 | 297
Related allowance | 40 | 37
Commercial: |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 63 | 68
Amortized cost basis with allowance | 90 | 90
Nonaccrual loans that are current | 153 | 158
Related allowance | 25 | 23
Commercial: | Commercial and industrial |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 50 | 45
Amortized cost basis with allowance | 57 | 69
Nonaccrual loans that are current | 107 | 114
Related allowance | 22 | 19
Commercial: | Owner-occupied |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 13 | 18
Amortized cost basis with allowance | 27 | 13
Nonaccrual loans that are current | 40 | 31
Related allowance | 2 | 1
Commercial: | Municipal |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 0 | 5
Amortized cost basis with allowance | 2 | 6
Nonaccrual loans that are current | 2 | 11
Related allowance | 0 | 2
Commercial: | Leasing |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 0 | 0
Amortized cost basis with allowance | 4 | 2
Nonaccrual loans that are current | 4 | 2
Related allowance | 1 | 1
Commercial real estate: |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 1 | 27
Amortized cost basis with allowance | 69 | 32
Nonaccrual loans that are current | 70 | 59
Related allowance | 3 | 4
Commercial real estate: | Term |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 1 | 27
Amortized cost basis with allowance | 69 | 32
Nonaccrual loans that are current | 70 | 59
Related allowance | 3 | 4
Consumer: |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 11 | 17
Amortized cost basis with allowance | 85 | 63
Nonaccrual loans that are current | 96 | 80
Related allowance | 12 | 10
Consumer: | 1-4 family residential |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 11 | 12
Amortized cost basis with allowance | 52 | 37
Nonaccrual loans that are current | 63 | 49
Related allowance | 4 | 4
Consumer: | Home equity credit line |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 0 | 5
Amortized cost basis with allowance | 32 | 25
Nonaccrual loans that are current | 32 | 30
Related allowance | 7 | 5
Consumer: | Bankcard and other revolving plans |  |
Financing Receivable, Allowance for Credit Losses [Line Items] |  |
Amortized cost basis with no allowance | 0 | 0
Amortized cost basis with allowance | 1 | 1
Nonaccrual loans that are current | 1 | 1
Related allowance | $ 1 | $ 1

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