LOANS AND LEASES - Schedule of Loans Pledged as Collateral (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024	Sep. 30, 2024
FHLB of Atlanta
Pledged non-PCD loans	$ 144,758	$ 140,221	$ 138,695
FHLB of Atlanta \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Lendable collateral value of pledged non-PCD loans	19,472	17,873
Less: advances	0	0
Less: letters of credit	1,450	1,450
Available borrowing capacity	18,022	16,423
Pledged non-PCD loans	31,945	30,421
FRB \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans	13,804	6,309
FRB
Lendable collateral value of pledged non-PCD loans	13,328	5,475
Less: advances	0	0
Available borrowing capacity	13,328	5,475
FDIC \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans	34,860	41,040
FDIC
Lendable collateral value of pledged loans	36,228	41,282
Less: advances	0	0
Less: Purchase Money Note	35,991	35,991
Available borrowing capacity	$ 0	$ 5,291

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