Related Party Transactions - Summary of Related Party Transactions (Details) - USD ($) $ in Millions		Dec. 31, 2015		Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Assets:
Cash and due from banks		$ 968		$ 891		$ 961	$ 1,359
Interest bearing deposits with banks		7,478		30,807
Securities purchased under agreements to resell		19,847		1,413
Trading assets		17,085		21,092
Loans		82,917		77,741		67,695
Other assets		6,890		7,989
Total assets		188,278	[1]	185,539	[1]	185,487
Liabilities:
Deposits		118,579	[2]	116,118	[2]	112,608
Trading liabilities		7,455		8,164
Short-term borrowings		4,995		12,795		19,135
Long-term debt		33,509		27,524
Other		3,215		3,971
Total liabilities	[1]	167,753		168,572
Affiliated Entity [Member]
Assets:
Cash and due from banks		169		140
Interest bearing deposits with banks		244		928
Securities purchased under agreements to resell	[3]	4,000		0
Trading assets	[4]	18,632		20,194
Loans		4,815		4,821		$ 5,328
Other assets	[5]	458		983
Total assets		28,318		27,066
Liabilities:
Deposits		13,486		16,596
Trading liabilities	[4]	19,496		21,130
Short-term borrowings		2,004		847
Long-term debt		1,827		3,981
Other	[5]	346		459
Total liabilities		$ 37,159		$ 43,013

[1] The following table summarizes assets and liabilities related to our consolidated variable interest entities ("VIEs") as of December 31, 2015 and December 31, 2014 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. See Note 24, "Variable Interest Entities," for additional information. Assets: Other assets $320 million and $380 million. Total assets $320 million and $380 million respectively. Liabilities: Long-term debt $92 million and $92 million, Interest, taxes and other liabilities $68 million and $75 million. Total liabilities $160 million and $167 million, respectively.

[2] During the second quarter of 2015, we concluded that brokered deposits would be better presented as debt under the Group Reporting Basis. As a result, we reclassified $3.7 billion of brokered deposits in the GB&M segment to debt at December 31, 2014 to conform with the current year presentation. There was no impact at December 31, 2013.

[3] Reflects overnight purchases of U.S. Treasury securities which HSBC Securities (USA) Inc. ("HSI") has agreed to repurchase.

[4] Trading assets and trading liabilities do not reflect the impact of netting which allows the offsetting of amounts relating to certain contracts if certain conditions are met. Trading assets and liabilities primarily consist of derivatives contracts.

[5] Other assets and other liabilities primarily consist of derivative contracts.