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LOANS AND LEASES - Schedule of Loans to Related Parties (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2025 USD ($)
Financing Receivable, Excluding Accrued Interest [Roll Forward] |  |
Balance at Beginning of Year | $ 33,939 | [1]
Balance at End of Year | 34,777 | [1]
Related Party |  |
Financing Receivable, Excluding Accrued Interest [Roll Forward] |  |
Balance at Beginning of Year | 6 |
New loans | 4 |
Repayments | (2) |
Other | (1) |
Balance at End of Year | $ 7 |
[1] | Amount represents loans for which we have elected the fair value option. See Note 25.

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