v3.26.1
AFS and HTM Debt Securities, Gross Unrealized Losses and Fair Value (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale $ (1,337) $ (995)
Less than 12 months, Fair value, available-for-sale 83,269 13,305
12 months or more, Gross unrealized losses, available-for-sale (3,198) (2,996)
12 months or more, Fair value, available-for-sale 35,049 50,012
Total, Gross unrealized losses, available-for-sale (4,535) (3,991)
Total Fair value, available for sale 118,318 63,317
Securities of U.S. Treasury and federal agencies [Member]    
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale (29) 0
Less than 12 months, Fair value, available-for-sale 22,926 0
12 months or more, Gross unrealized losses, available-for-sale (200) (237)
12 months or more, Fair value, available-for-sale 5,340 6,119
Total, Gross unrealized losses, available-for-sale (229) (237)
Total Fair value, available for sale 28,266 6,119
Securities of U.S. states and political subdivisions [Member]    
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale (6) (5)
Less than 12 months, Fair value, available-for-sale 913 222
12 months or more, Gross unrealized losses, available-for-sale (301) (338)
12 months or more, Fair value, available-for-sale 4,587 5,701
Total, Gross unrealized losses, available-for-sale (307) (343)
Total Fair value, available for sale 5,500 5,923
Federal agency mortgage-backed securities [Member]    
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale (1,301) (988)
Less than 12 months, Fair value, available-for-sale 57,913 11,307
12 months or more, Gross unrealized losses, available-for-sale (2,684) (2,401)
12 months or more, Fair value, available-for-sale 24,857 37,377
Total, Gross unrealized losses, available-for-sale (3,985) (3,389)
Total Fair value, available for sale 82,770 48,684
Non-agency mortgage-backed securities [Member]    
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale 0 0
Less than 12 months, Fair value, available-for-sale 0 0
12 months or more, Gross unrealized losses, available-for-sale (10) (18)
12 months or more, Fair value, available-for-sale 248 744
Total, Gross unrealized losses, available-for-sale (10) (18)
Total Fair value, available for sale 248 744
Collateralized loan obligations [Member]    
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale (1) (2)
Less than 12 months, Fair value, available-for-sale 1,517 1,776
12 months or more, Gross unrealized losses, available-for-sale 0 0
12 months or more, Fair value, available-for-sale 0 0
Total, Gross unrealized losses, available-for-sale (1) (2)
Total Fair value, available for sale 1,517 1,776
Other debt securities [Member]    
Available-for-sale debt securities:    
Less than 12 months, Gross unrealized losses, available-for-sale 0 0
Less than 12 months, Fair value, available-for-sale 0 0
12 months or more, Gross unrealized losses, available-for-sale (3) (2)
12 months or more, Fair value, available-for-sale 17 71
Total, Gross unrealized losses, available-for-sale (3) (2)
Total Fair value, available for sale $ 17 $ 71