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LOANS AND LEASES - Schedule of Loans Pledged as Collateral (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
FHLB of Atlanta
Pledged non-PCD loans	$ 147,930	$ 140,221	$ 133,302
FHLB of Atlanta | Non-PCD | Asset Pledged as Collateral
FHLB of Atlanta
Lendable collateral value of pledged non-PCD loans	19,225	17,873
Less: advances	0	0
Less: letters of credit	1,450	1,450
Available borrowing capacity	17,775	16,423
Pledged non-PCD loans	31,713	30,421
FRB | Non-PCD | Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans	13,640	6,309
FRB
Lendable collateral value of pledged non-PCD loans	12,962	5,475
Less: advances	0	0
Available borrowing capacity	12,962	5,475
FDIC | Asset Pledged as Collateral
FHLB of Atlanta
Pledged non-PCD loans	34,465	41,040
FDIC
Lendable collateral value of pledged loans	35,705	41,282
Less: advances	0	0
Less: principal amount of the Purchase Money Note	33,500	35,991
Available borrowing capacity	$ 0	$ 5,291

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