FAIR VALUE (Schedule of Carrying Values and Estimated Fair Values of Financial Instruments) (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Held-to-maturity investment securities	$ 8,696	$ 8,940
Financial liabilities:
Time deposits	9,661	9,907
Level 2 \| Carrying value \| Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Held-to-maturity investment securities	8,688	8,867
Financial liabilities:
Time deposits	9,661	9,907
Long-term debt	1,963	1,472
Level 2 \| Fair value \| Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Held-to-maturity investment securities	8,696	8,940
Financial liabilities:
Time deposits	9,571	9,839
Long-term debt	1,974	1,506
Level 3 \| Carrying value \| Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases (including loans held for sale), net of allowance	60,785	60,423
Level 3 \| Fair value \| Fair Value, Nonrecurring
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Loans and leases (including loans held for sale), net of allowance	$ 59,775	$ 59,383

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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