LOANS, LEASES, AND ALLOWANCE FOR CREDIT LOSSES (Summary of Nonaccrual Loans) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	$ 93	$ 95
Amortized cost basis with allowance	186	220
Nonaccrual loans that are current	279	315
Related allowance	39	36
Commercial:
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	56	77
Amortized cost basis with allowance	79	69
Nonaccrual loans that are current	135	146
Related allowance	22	20
Commercial: \| Commercial and industrial
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	38	44
Amortized cost basis with allowance	45	49
Nonaccrual loans that are current	83	93
Related allowance	20	19
Commercial: \| Owner-occupied
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	18	33
Amortized cost basis with allowance	32	18
Nonaccrual loans that are current	50	51
Related allowance	2	1
Commercial: \| Municipal
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	0	0
Amortized cost basis with allowance	2	2
Nonaccrual loans that are current	2	2
Related allowance	0	0
Commercial: \| Leasing
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance		0
Amortized cost basis with allowance		0
Nonaccrual loans that are current		0
Related allowance		0
Commercial real estate:
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	23	4
Amortized cost basis with allowance	19	69
Nonaccrual loans that are current	42	73
Related allowance	1	2
Commercial real estate: \| Term
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	23	4
Amortized cost basis with allowance	19	68
Nonaccrual loans that are current	42	72
Related allowance	1	2
Commercial real estate: \| Construction and land development
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance		0
Amortized cost basis with allowance		1
Nonaccrual loans that are current		1
Related allowance		0
Consumer:
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	14	14
Amortized cost basis with allowance	88	82
Nonaccrual loans that are current	102	96
Related allowance	16	14
Consumer: \| 1-4 family residential
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	14	14
Amortized cost basis with allowance	53	51
Nonaccrual loans that are current	67	65
Related allowance	6	5
Consumer: \| Home equity credit line
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	0	0
Amortized cost basis with allowance	33	30
Nonaccrual loans that are current	33	30
Related allowance	9	8
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
Consumer: \| Other
Financing Receivable, Allowance for Credit Losses [Line Items]
Amortized cost basis with no allowance	0
Amortized cost basis with allowance	1
Nonaccrual loans that are current	1
Related allowance	$ 0

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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-Publisher SEC

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