v3.22.0.1
Fair Value Disclosures - Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Millions
Dec. 31, 2021
Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Trading securities $ 1,186 $ 1,964
Equity securities/mutual funds 1,738 2,317
Separate account assets 86,226 104,663
Separate account collateral liabilities under securities lending agreements 7,081 16,507
Investments Measured at NAV [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Other assets 22 69
Equity securities [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Equity securities/mutual funds 1,738 2,317
Fair Value, Measurements, Recurring [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Held-to-maturity investments 430 310
Total debt securities 1,616 2,274
Total equity method 1,694 1,081
Bank loans 284 248
Federal Reserve Bank Stock 96 94
Carried interest 1,555 627
Other investments 279 278
Total investments 7,262 6,919
Other assets 234 218
Separate account assets 86,226 104,663
Total separate account collateral held under securities lending agreements 7,081 16,507
Total 100,803 128,307
Separate account collateral liabilities under securities lending agreements 7,081 16,507
Other liabilities 368 340
Total liabilities measured at fair value 7,449 16,847
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 245 235
Total investments 1,983 2,552
Other assets 195 205
Separate account assets 54,675 71,392
Total separate account collateral held under securities lending agreements 3,717 13,126
Total 60,570 87,275
Separate account collateral liabilities under securities lending agreements 3,717 13,126
Total liabilities measured at fair value 3,717 13,126
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total debt securities 1,169 1,953
Bank loans 14 16
Total investments 1,183 1,969
Other assets 39 13
Separate account assets 30,786 32,404
Total separate account collateral held under securities lending agreements 3,364 3,381
Total 35,372 37,767
Separate account collateral liabilities under securities lending agreements 3,364 3,381
Other liabilities 26 68
Total liabilities measured at fair value 3,390 3,449
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total debt securities 17 11
Bank loans 270 232
Other investments 5 9
Total investments 292 252
Total 292 252
Other liabilities 342 272
Total liabilities measured at fair value 342 272
Fair Value, Measurements, Recurring [Member] | Debt Securities/ Fixed Income Mutual Funds [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Trading securities 1,186 1,964
Fair Value, Measurements, Recurring [Member] | Debt Securities/ Fixed Income Mutual Funds [Member] | Significant Other Observable Inputs (Level 2) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Trading securities 1,169 1,953
Fair Value, Measurements, Recurring [Member] | Debt Securities/ Fixed Income Mutual Funds [Member] | Significant Unobservable Inputs (Level 3) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Trading securities 17 11
Fair Value, Measurements, Recurring [Member] | Equity Securities/Mutual Funds [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Equity securities/mutual funds 1,738 2,317
Fair Value, Measurements, Recurring [Member] | Equity Securities/Mutual Funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Equity securities/mutual funds 1,738 2,317
Fair Value, Measurements, Recurring [Member] | Equity And Fixed Income Mutual Funds [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 245 235
Fair Value, Measurements, Recurring [Member] | Equity And Fixed Income Mutual Funds [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 245 235
Fair Value, Measurements, Recurring [Member] | Hedge Funds/Funds of Hedge Funds [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 369 313
Fair Value, Measurements, Recurring [Member] | Private/ Public Equity [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 846 315
Fair Value, Measurements, Recurring [Member] | Real Assets Funds [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 234 218
Fair Value, Measurements, Recurring [Member] | Investments Measured at NAV [Member] | Investment in NAV [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 1,449 846
Other investments 96 94
Total investments 1,545 940
Total 1,545 940
Fair Value, Measurements, Recurring [Member] | Investments Measured at NAV [Member] | Hedge Funds/Funds of Hedge Funds [Member] | Investment in NAV [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 369 313
Fair Value, Measurements, Recurring [Member] | Investments Measured at NAV [Member] | Private/ Public Equity [Member] | Investment in NAV [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 846 315
Fair Value, Measurements, Recurring [Member] | Investments Measured at NAV [Member] | Real Assets Funds [Member] | Investment in NAV [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total equity method 234 218
Fair Value, Measurements, Recurring [Member] | Other [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Held-to-maturity investments 430 310
Total debt securities 430 310
Federal Reserve Bank Stock 96 94
Carried interest 1,555 627
Other investments 178 175
Total investments 2,259 1,206
Separate account assets 765 867
Total 3,024 2,073
Fair Value, Measurements, Recurring [Member] | Equity securities [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total separate account collateral held under securities lending agreements 3,717 13,126
Fair Value, Measurements, Recurring [Member] | Equity securities [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total separate account collateral held under securities lending agreements 3,717 13,126
Fair Value, Measurements, Recurring [Member] | Debt securities [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total separate account collateral held under securities lending agreements 3,364 3,381
Fair Value, Measurements, Recurring [Member] | Debt securities [Member] | Significant Other Observable Inputs (Level 2) [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Total separate account collateral held under securities lending agreements $ 3,364 $ 3,381