v3.25.1
Securities - Gross Unrealized Losses and Related Fair Values (Detail)
$ in Millions
Mar. 31, 2025
USD ($)
security
Dec. 31, 2024
USD ($)
security
Debt Securities, Available-for-sale [Line Items]    
Number of securities available for sale in one year or less | security 38 40
Securities available-for-sale gross unrealized losses one year or less $ (24) $ (45)
Securities available-for-sale aggregate fair value of investment one year or less $ 8,120 $ 6,462
Number of Securities available for sale greater than one year | security 317 319
Securities available-for-sale gross unrealized losses greater than one year $ (2,026) $ (2,253)
Securities available-for-sale aggregate fair value of investment greater than one year $ 14,559 $ 14,384
U.S. Treasury    
Debt Securities, Available-for-sale [Line Items]    
Number of securities available for sale in one year or less | security 16 14
Securities available-for-sale gross unrealized losses one year or less $ (6) $ (15)
Securities available-for-sale aggregate fair value of investment one year or less $ 5,017 $ 3,402
Number of Securities available for sale greater than one year | security 39 38
Securities available-for-sale gross unrealized losses greater than one year $ (168) $ (190)
Securities available-for-sale aggregate fair value of investment greater than one year $ 4,313 $ 4,055
U.S. Government sponsored enterprises    
Debt Securities, Available-for-sale [Line Items]    
Number of securities available for sale in one year or less | security 0 0
Securities available-for-sale gross unrealized losses one year or less $ 0 $ 0
Securities available-for-sale aggregate fair value of investment one year or less $ 0 $ 0
Number of Securities available for sale greater than one year | security 134 137
Securities available-for-sale gross unrealized losses greater than one year $ (941) $ (1,008)
Securities available-for-sale aggregate fair value of investment greater than one year $ 3,758 $ 3,871
U.S. Government agency issued or guaranteed    
Debt Securities, Available-for-sale [Line Items]    
Number of securities available for sale in one year or less | security 4 4
Securities available-for-sale gross unrealized losses one year or less $ (17) $ (28)
Securities available-for-sale aggregate fair value of investment one year or less $ 525 $ 526
Number of Securities available for sale greater than one year | security 137 137
Securities available-for-sale gross unrealized losses greater than one year $ (906) $ (1,043)
Securities available-for-sale aggregate fair value of investment greater than one year $ 6,293 $ 6,311
Asset-backed securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities available for sale in one year or less | security 1 0
Securities available-for-sale gross unrealized losses one year or less $ 0 $ 0
Securities available-for-sale aggregate fair value of investment one year or less $ 50 $ 0
Number of Securities available for sale greater than one year | security 6 6
Securities available-for-sale gross unrealized losses greater than one year $ (11) $ (12)
Securities available-for-sale aggregate fair value of investment greater than one year $ 95 $ 97
Foreign debt securities    
Debt Securities, Available-for-sale [Line Items]    
Number of securities available for sale in one year or less | security 17 22
Securities available-for-sale gross unrealized losses one year or less $ (1) $ (2)
Securities available-for-sale aggregate fair value of investment one year or less $ 2,528 $ 2,534
Number of Securities available for sale greater than one year | security 1 1
Securities available-for-sale gross unrealized losses greater than one year $ 0 $ 0
Securities available-for-sale aggregate fair value of investment greater than one year $ 100 $ 50