XML 57 R43.htm IDEA: XBRL DOCUMENT v3.21.2
Investment Securities - Available-for-Sale (Detail) - USD ($)
$ in Millions
Sep. 30, 2021
Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost $ 149,238 [1] $ 133,611
Available-for-sale securities, Unrealized Gains 1,868 3,282
Available-for-sale securities, Unrealized Losses (1,730) (53)
Available-for-sale securities, Fair Value [2] 149,376 [1] 136,840
U.S. Treasury and Agencies [Member]    
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost 18,460 21,954
Available-for-sale securities, Unrealized Gains 230 462
Available-for-sale securities, Unrealized Losses (199) (25)
Available-for-sale securities, Fair Value 18,491 22,391
Residential Mortgage-Backed Securities [Member] | Agency [Member]    
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost 113,137 98,031
Available-for-sale securities, Unrealized Gains 996 1,950
Available-for-sale securities, Unrealized Losses (1,337) (13)
Available-for-sale securities, Fair Value 112,796 99,968
Commercial [Member] | Agency [Member]    
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost 7,750 5,251
Available-for-sale securities, Unrealized Gains 77 170
Available-for-sale securities, Unrealized Losses (141) (15)
Available-for-sale securities, Fair Value 7,686 5,406
Asset-Backed Securities [Member]    
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost 64 [3] 200
Available-for-sale securities, Unrealized Gains 5 5
Available-for-sale securities, Fair Value 69 [3] 205
Obligations of State and Political Subdivisions [Member]    
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost 9,820 [4],[5] 8,166
Available-for-sale securities, Unrealized Gains 560 695
Available-for-sale securities, Unrealized Losses (53)  
Available-for-sale securities, Fair Value 10,327 [4],[5] 8,861
Other [Member]    
Debt Securities, Available-for-sale [Line Items]    
Available-for-sale Securities, Amortized Cost 7 9
Available-for-sale securities, Fair Value $ 7 $ 9
[1] The weighted-average maturity of total available-for-sale investment securities was 3.4 years at December 31, 2020, with a corresponding weighted-average yield of 1.61 percent.
[2] Includes only collateral pledged by the Company where counterparties have the right to sell or pledge the collateral.
[3] Information related to asset and mortgage-backed securities included above is presented based upon weighted-average maturities that take into account anticipated future prepayments.
[4] Information related to obligations of state and political subdivisions is presented based upon yield to first optional call date if the security is purchased at a premium, and yield to maturity if the security is purchased at par or a discount.
[5] Maturity calculations for obligations of state and political subdivisions are based on the first optional call date for securities with a fair value above par and the contractual maturity date for securities with a fair value equal to or below par.