v3.26.1
Fair Value Disclosures - Changes in Level 3 Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance $ 377 $ 338 $ 367 $ 363
Realized and Unrealized Gains (Losses),Assets 9 11 0 1
Purchases, Assets 39 5 67 20
Sales and Maturities, Assets (168) (19) (177) (49)
Issuances and other Settlements, Assets 0 0 0 0
Transfers into Level 3, Assets 23 0 23 0
Transfers out of Level 3, Assets (5) 0 (5) 0
Assets measured at fair value, ending balance 275 335 275 335
Total Net Unrealized Gains (Losses) Included in Earnings 9 11 0 1
Liabilities measured at fair value, beginning balance   4,492   4,431
Realized and Unrealized Gains (Losses), Liabilities   82   178
Purchases, Liabilities   0   0
Sales and Maturities, Liabilities   0   0
Issuances and other Settlements, Liabilities   (5)   (40)
Transfers into Level 3, Liabilities   0   0
Transfers out of Level 3, Liabilities   0   0
Liabilities measured at fair value, ending balance   4,569   4,569
Total Net Unrealized Gains (Losses) Included in Earnings   82   178
Other Assets [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance 149 152 151 149
Assets measured at fair value, ending balance 149 164 149 164
Other Liabilities [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Liabilities measured at fair value, beginning balance   102   129
Liabilities measured at fair value, ending balance   97   97
Contingent Consideration Liabilities [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Liabilities measured at fair value, beginning balance 7,865 4,390 8,429 4,302
Realized and Unrealized Gains (Losses), Liabilities $ 10 $ 82 $ (541) $ 181
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Business Combination, Contingent Consideration, Liability, Current Business Combination, Contingent Consideration, Liability, Current Business Combination, Contingent Consideration, Liability, Current Business Combination, Contingent Consideration, Liability, Current
Purchases, Liabilities $ 0 $ 0 $ 0 $ 0
Sales and Maturities, Liabilities 0 0 0 0
Issuances and other Settlements, Liabilities 0 0 (13) (11)
Transfers into Level 3, Liabilities 0 0 0 0
Transfers out of Level 3, Liabilities 0 0 0 0
Liabilities measured at fair value, ending balance 7,875 4,472 7,875 4,472
Total Net Unrealized Gains (Losses) Included in Earnings 10 82 (541) 181
Investments [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance 228 186 216 214
Realized and Unrealized Gains (Losses),Assets 9 (1) 2 (14)
Purchases, Assets 39 5 67 20
Sales and Maturities, Assets (168) (19) (177) (49)
Issuances and other Settlements, Assets 0 0 0 0
Transfers into Level 3, Assets 23 0 23 0
Transfers out of Level 3, Assets (5) 0 (5) 0
Assets measured at fair value, ending balance 126 171 126 171
Total Net Unrealized Gains (Losses) Included in Earnings 9 (1) 2 (14)
Debt securities [Member] | Trading [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance 35 79 7 79
Realized and Unrealized Gains (Losses),Assets 0 (3) 0 (5)
Purchases, Assets 30 1 58 5
Sales and Maturities, Assets (26) (1) (26) (3)
Issuances and other Settlements, Assets 0 0 0 0
Transfers into Level 3, Assets 7 0 7 0
Transfers out of Level 3, Assets 0 (1) 0 (1)
Assets measured at fair value, ending balance 46 75 46 75
Total Net Unrealized Gains (Losses) Included in Earnings $ 0 $ (3) $ 0 $ (5)
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] Nonoperating Income (Expense) Nonoperating Income (Expense) Nonoperating Income (Expense) Nonoperating Income (Expense)
Mutual Funds [Member] | Equity Securities Mutual Funds [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance $ 136   $ 136  
Realized and Unrealized Gains (Losses),Assets 4   4  
Purchases, Assets 6   6  
Sales and Maturities, Assets (136)   (136)  
Issuances and other Settlements, Assets 0   0  
Transfers into Level 3, Assets 14   14  
Transfers out of Level 3, Assets 0   0  
Assets measured at fair value, ending balance 24   24  
Total Net Unrealized Gains (Losses) Included in Earnings 4   4  
Loans [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance 57   73  
Realized and Unrealized Gains (Losses),Assets 5   (2)  
Purchases, Assets 3   3  
Sales and Maturities, Assets (6)   (15)  
Issuances and other Settlements, Assets 0   0  
Transfers into Level 3, Assets 2   2  
Transfers out of Level 3, Assets (5)   (5)  
Assets measured at fair value, ending balance 56   56  
Total Net Unrealized Gains (Losses) Included in Earnings 5   (2)  
Consolidated Variable Interest Entities [Member] | Loans [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Assets measured at fair value, beginning balance   $ 107   $ 135
Realized and Unrealized Gains (Losses),Assets   2   (9)
Purchases, Assets   4   15
Sales and Maturities, Assets   (18)   (46)
Issuances and other Settlements, Assets   0   0
Transfers into Level 3, Assets   0   0
Transfers out of Level 3, Assets   1   1
Assets measured at fair value, ending balance   96   96
Total Net Unrealized Gains (Losses) Included in Earnings   2   (9)
Other Assets One [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Realized and Unrealized Gains (Losses),Assets 0 12 (2) 15
Purchases, Assets 0 0 0
Sales and Maturities, Assets 0 0 0 0
Issuances and other Settlements, Assets 0 0 0 0
Transfers into Level 3, Assets 0 0
Transfers out of Level 3, Assets 0 0 0 0
Total Net Unrealized Gains (Losses) Included in Earnings $ 0 12 $ (2) 15
Other Liabilities One [Member]        
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]        
Realized and Unrealized Gains (Losses), Liabilities   0   (3)
Purchases, Liabilities   0   0
Sales and Maturities, Liabilities   0   0
Issuances and other Settlements, Liabilities   (5)   (29)
Transfers into Level 3, Liabilities   0   0
Transfers out of Level 3, Liabilities   0   0
Total Net Unrealized Gains (Losses) Included in Earnings   $ 0   $ (3)
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]   Nonoperating Income (Expense)   Nonoperating Income (Expense)