v3.26.1
Accumulated Other Comprehensive Income - Schedule of Changes in 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 $ 19,987 $ 19,003 $ 20,381 $ 18,176
Other comprehensive income before reclassification, net of income taxes (155) 215 (446) 828
Amounts reclassified from AOCI, net of income taxes 22 71 52 141
Total other comprehensive income (loss), net of tax (133) 286 (394) 969
Ending balance 19,798 19,484 19,798 19,484
Accumulated Other Comprehensive Income (Loss)        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance (2,221) (2,787) (1,960) (3,470)
Ending balance (2,354) (2,501) (2,354) (2,501)
Unrealized gains (losses) on securities available for sale        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance (1,888) (2,310) (1,716) (2,734)
Other comprehensive income before reclassification, net of income taxes (51) 152 (223) 576
Amounts reclassified from AOCI, net of income taxes 0 0 0 0
Total other comprehensive income (loss), net of tax (51) 152 (223) 576
Ending balance (1,939) (2,158) (1,939) (2,158)
Unrealized gains (losses) on derivative financial instruments        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance (98) (241) (7) (434)
Other comprehensive income before reclassification, net of income taxes (103) 64 (223) 186
Amounts reclassified from AOCI, net of income taxes 20 69 49 140
Total other comprehensive income (loss), net of tax (83) 133 (174) 326
Ending balance (181) (108) (181) (108)
Net pension and postretirement benefit costs        
AOCI Attributable to Parent, Net of Tax [Roll Forward]        
Beginning balance (235) (236) (237) (302)
Other comprehensive income before reclassification, net of income taxes (1) (1) 0 66
Amounts reclassified from AOCI, net of income taxes 2 2 3 1
Total other comprehensive income (loss), net of tax 1 1 3 67
Ending balance $ (234) $ (235) $ (234) $ (235)