Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Millions		Mar. 31, 2024		Dec. 31, 2023		Mar. 31, 2023
Assets:
Cash and due from banks	[1]	$ 695		$ 704
Interest bearing deposits with banks	[1]	30,687		25,015
Securities purchased under agreements to resell	[1]	8,306		13,878
Trading assets	[1]	18,900		22,115
Loans, net		59,216	[1]	58,396	[1]	$ 58,874
Other	[1]	7,332		6,490
Total assets		166,966	[1]	168,238	[1]	166,550
Liabilities:
Deposits		122,053	[1]	121,283	[1]	$ 122,168
Trading liabilities	[1]	2,546		3,485
Short-term borrowings	[1]	7,033		9,914
Long-term debt	[1]	19,439		18,661
Other	[1]	4,139		3,256
Total liabilities	[1]	155,210		156,599
Related Party
Assets:
Cash and due from banks		166		133
Interest bearing deposits with banks		14		90
Securities purchased under agreements to resell		11		406
Trading assets		80		57
Loans, net		3,442		2,618
Other		1,141		491
Total assets		4,854		3,795
Liabilities:
Deposits		14,915		9,110
Trading liabilities		78		321
Short-term borrowings		608		1,014
Long-term debt		6,508		6,511
Other		267		331
Total liabilities		$ 22,376		$ 17,287

[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