v3.26.3
LONG-TERM DEBT AND SHAREHOLDERS' EQUITY (Amounts Reclassified from AOCI) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Securities gains (losses), net $ (4) $ 11 $ 268 $ 31
Interest and fees on loans; Interest on short- and long-term borrowings 877 898 2,577 2,623
Less: Income tax expense (benefit) 73 63 264 200
Net income 263 222 949 636
Net unrealized gains (losses) on investment securities | Amounts reclassified from AOCI        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Securities gains (losses), net (58) (62) (168) (182)
Less: Income tax expense (benefit) (14) (15) (41) (45)
Net income (44) (47) (127) (137)
Net unrealized gains (losses) on derivatives and other | Amounts reclassified from AOCI        
Accumulated Other Comprehensive Income (Loss) [Line Items]        
Interest and fees on loans; Interest on short- and long-term borrowings (10) (15) (33) (52)
Less: Income tax expense (benefit) (2) (4) (8) (13)
Net income $ (8) $ (11) $ (25) $ (39)