LOANS AND LEASES - Schedule of Loans Pledged as Collateral (Details) - USD ($) $ in Millions	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
FHLB of Atlanta
Pledged non-PCD loans (contractual balance)	$ 138,695	$ 133,302	$ 133,202
FHLB of Atlanta \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Lendable collateral value of pledged non-PCD loans	17,245	15,072
Less: advances	0	0
Less: letters of credit	1,450	1,450
Available borrowing capacity	15,795	13,622
Pledged non-PCD loans (contractual balance)	30,106	25,370
FRB \| Non-PCD \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans (contractual balance)	6,689	6,273
FRB
Lendable collateral value of pledged non-PCD loans	5,621	5,115
Less: advances	0	0
Available borrowing capacity	5,621	5,115
FDIC \| Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans (contractual balance)	44,117	51,179
FDIC
Lendable collateral value of pledged loans	44,117	51,179
Less: advances	0	0
Less: Purchase Money Note	35,991	36,072
Available borrowing capacity	$ 8,126	$ 15,107

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