LOANS AND LEASES - Schedule of Loans Pledged as Collateral (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025	Sep. 30, 2025
FHLB of Atlanta
Pledged Non-PCD loans	$ 157,190	$ 147,930	$ 144,758
FHLB of Atlanta \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Lendable collateral value of pledged Non-PCD loans	19,323	19,225
Less: advances	0	0
Less: letters of credit	1,450	1,450
Available borrowing capacity	17,873	17,775
Pledged Non-PCD loans	32,329	31,713
FRB \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged Non-PCD loans	13,862	13,640
FRB
Lendable collateral value of pledged Non-PCD loans	13,227	12,962
Less: advances	0	0
Available borrowing capacity	13,227	12,962
FDIC \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged Non-PCD loans	30,588	34,465
FDIC
Lendable collateral value of pledged loans	31,708	35,705
Less: advances	0	0
Less: principal amount of the Purchase Money Note	20,500	33,500
Available borrowing capacity	$ 0	$ 0

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Advances from Federal Reserve Bank

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Letters Of Credit From Federal Home Loan Bank

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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