Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Summary of Pledged Assets Included in Consolidated Balance Sheet (Detail) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023		Mar. 31, 2023
Financial Instruments Owned and Pledged as Collateral [Line Items]
Interest bearing deposits with banks	[1]	$ 30,687		$ 25,015
Trading assets	[1]	18,900		22,115
Fair Value	[1]	25,550		25,696
Securities held-to-maturity	[1]	15,294		15,076
Loans, net	[1]	59,797		58,987
Other assets	[1]	7,332		6,490
Total assets		166,966	[1]	168,238	[1]	$ 166,550
Asset Pledged as Collateral
Financial Instruments Owned and Pledged as Collateral [Line Items]
Interest bearing deposits with banks		407		998
Trading assets		2,472		3,046
Fair Value		9,829		9,773
Securities held-to-maturity		5,197		5,387
Loans, net		20,778		18,810
Other assets		908		934
Total assets		$ 39,591		$ 38,948

[1] The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at March 31, 2024 and December 31, 2023. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 15, "Variable Interest Entities," for additional information. March 31, 2024December 31, 2023(in millions)AssetsOther assets$21 $23 Total assets$21 $23 LiabilitiesInterest, taxes and other liabilities$28 $17 Total liabilities$28 $17