v3.26.1
Fair Value Hierarchy - Summary of Changes in Fair Value for Level 3 Trading Cash Instruments (Detail) - USD ($)
$ in Millions
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Assets    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance $ 904 $ 1,213
Net realized gains/(losses) 38 32
Net unrealized gains/(losses) (62) (12)
Purchases 202 273
Sales (86) (222)
Settlements (82) (312)
Transfers into level 3 420 179
Transfers out of level 3 (129) (137)
Ending balance 1,205 1,014
Assets | Loans and securities backed by real estate    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 155 95
Net realized gains/(losses) 1 1
Net unrealized gains/(losses) 0 1
Purchases 3 1
Sales 0 (2)
Settlements (16) (3)
Transfers into level 3 28 8
Transfers out of level 3 (4) (33)
Ending balance 167 68
Assets | Corporate debt instruments    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 484 728
Net realized gains/(losses) 28 26
Net unrealized gains/(losses) (52) (11)
Purchases 152 206
Sales (72) (111)
Settlements (53) (295)
Transfers into level 3 360 152
Transfers out of level 3 (111) (74)
Ending balance 736 621
Assets | Other    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance 265 390
Net realized gains/(losses) 9 5
Net unrealized gains/(losses) (10) (2)
Purchases 47 66
Sales (14) (109)
Settlements (13) (14)
Transfers into level 3 32 19
Transfers out of level 3 (14) (30)
Ending balance 302 325
Liabilities    
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Beginning balance (119) (75)
Net unrealized gains/(losses) 3 (10)
Purchases 28 23
Sales (17) (77)
Settlements 26 (1)
Transfers into level 3 (9) (7)
Transfers out of level 3 29 14
Ending balance $ (59) $ (133)