v3.26.1
ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Schedule of Changes in Components of AOCI (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance, shareholders' equity $ 22,048 $ 22,295 $ 22,238 $ 22,228
AOCI activity before reclassifications     (310) 334
Amounts reclassified from AOCI to earnings     (3) (3)
Other comprehensive income (loss) for the period (158) 85 (313) 331
Ending balance, shareholders' equity 21,900 22,296 21,900 22,296
Total accumulated other comprehensive (loss) income        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance, shareholders' equity (72) (199) 83 (445)
Other comprehensive income (loss) for the period (158) 85 (313) 331
Ending balance, shareholders' equity (230) (114) (230) (114)
Unrealized loss on securities available for sale        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance, shareholders' equity     (137) (584)
AOCI activity before reclassifications     (272) 328
Amounts reclassified from AOCI to earnings     0 0
Other comprehensive income (loss) for the period     (272) 328
Ending balance, shareholders' equity (409) (256) (409) (256)
Unrealized loss on securities available for sale transferred to held to maturity        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance, shareholders' equity     (4) (4)
AOCI activity before reclassifications     0 0
Amounts reclassified from AOCI to earnings     0 0
Other comprehensive income (loss) for the period     0 0
Ending balance, shareholders' equity (4) (4) (4) (4)
Defined benefit pension items        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance, shareholders' equity     210 135
AOCI activity before reclassifications (2) (3) (4) (3)
Amounts reclassified from AOCI to earnings (1) 0 (1) 0
Other comprehensive income (loss) for the period (3) (3) (5) (3)
Ending balance, shareholders' equity 205 132 205 132
Unrealized gain (loss) on cash flow hedge derivatives        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance, shareholders' equity     14 8
AOCI activity before reclassifications (20) (1) (34) 9
Amounts reclassified from AOCI to earnings (2) 0 (2) (3)
Other comprehensive income (loss) for the period (22) (1) (36) 6
Ending balance, shareholders' equity $ (22) $ 14 $ (22) $ 14