Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Millions		Mar. 31, 2019		Dec. 31, 2018		Mar. 31, 2018
Assets:
Cash and due from banks		$ 1,238		$ 1,514
Interest bearing deposits with banks		20,197		15,700
Trading assets		26,101		21,978
Loans		71,034		68,978		$ 67,338
Other		7,376		6,325
Total assets		180,921	[1]	172,448	[1]	182,035
Liabilities:
Deposits		113,639		110,955		117,953
Trading liabilities		3,908		3,643
Short-term borrowings		9,567		4,180
Long-term debt		31,475		30,628
Other		4,011		2,536
Total liabilities	[1]	162,600		151,942
Affiliated Entity [Member]
Assets:
Cash and due from banks		241		245
Interest bearing deposits with banks		978		1,000
Trading assets		27		102
Loans		2,688		2,274		$ 1,920
Other		623		169
Total assets		4,557		3,790
Liabilities:
Deposits		13,783		12,000
Trading liabilities		239		349
Short-term borrowings		736		638
Long-term debt		7,846		7,845
Other	[2]	350		333
Total liabilities		$ 22,954		$ 21,165

[1] The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") at March 31, 2019 and December 31, 2018 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 17, "Variable Interest Entities," for additional information. Assets: Other assets $106 million and $112 million. Total assets $106 million and $112 million respectively. Liabilities: Long-term debt $66 million and $66 million, Interest, taxes and other liabilities $36 million and $37 million. Total liabilities $102 million and $103 million, respectively.

[2] Other assets and other liabilities primarily consist of derivative balances associated with hedging activities and other miscellaneous account receivables and payables.