Guarantee Arrangements, Pledged Assets and Repurchase Agreements - Summary of Pledged Assets Included in Consolidated Balance Sheet (Detail) - USD ($) $ in Millions		Jun. 30, 2020	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Interest bearing deposits with banks	[1]	$ 3,509	$ 2,682
Trading assets	[2]	2,849	525
Securities available-for-sale	[3]	7,967	6,814
Securities held to maturity	[3]	1,363	1,688
Loans	[4]	14,842	14,342
Other assets	[5]	4,293	3,517
Total		$ 34,823	$ 29,568

[1] Represents gross amount of cash on deposit with banks related to derivative collateral-support agreements, of which a majority has been netted against derivative liabilities on the consolidated balance sheet.

[2] Trading assets are primarily pledged against liabilities associated with repurchase agreements.

[3] Securities are primarily pledged against derivatives, public fund deposits, trust deposits and various short-term and long term borrowings, as well as providing capacity for potential secured borrowings from the FHLB and the Federal Reserve Bank of New York.

[4] Loans are primarily residential mortgage loans pledged against current and potential borrowings from the FHLB and the Federal Reserve Bank of New York.

[5] Represents gross amount of cash on deposit with non-banks related to derivative collateral support agreements, of which a majority has been netted against derivative liabilities on the consolidated balance sheet.