Litigation and Regulatory Matters - Additional Information (Details) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended	0 Months Ended			1 Months Ended		0 Months Ended	12 Months Ended	36 Months Ended	12 Months Ended	1 Months Ended	0 Months Ended
	Sep. 30, 2011 officer	Jun. 30, 2013	Dec. 31, 2013	Oct. 29, 2014	Dec. 11, 2014	Sep. 12, 2014	Jun. 30, 2014 trust	Nov. 30, 2013	Feb. 28, 2013 mortgage_servicer	Dec. 31, 2012	Dec. 31, 2007	Dec. 31, 2014 trust	Dec. 31, 2012	Jan. 22, 2015	Jun. 05, 2013 class_action	Oct. 31, 2012 county	Feb. 29, 2012 state service	Dec. 31, 2011
Loss Contingencies [Line Items]
Insurance, variance to price threshold			20.00%
Estimate of loss												$ 50,000,000
Number of opt-out suits filed												35
Product Liability Accrual, Recoveries		6,000,000
Number Of Former And Current Officers And Directors	5
Diaz v. HSBC Bank USA, N.A., et al. [Member]
Loss Contingencies [Line Items]
Legal settlement amount				32,000,000
Weller, et. al. v. HSBC Mortgage Services Inc., et. al. [Member]
Loss Contingencies [Line Items]
Legal settlement amount					1,800,000
FHFA Litigation [Member]
Loss Contingencies [Line Items]
Legal settlement amount						550,000,000
Blackrock and PIMCO Funds [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value							32,000,000,000
Number of Identified Trusts							264
Deutche Bank Alleged Breach of Representation [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value								508,000,000
Foreclosure Practices [Member]
Loss Contingencies [Line Items]
Loss Contingency, Number of Mortgage Servicers									12
Loss Contingency, Threshold of Cash Payments, Mortgage Servicers Subject to Foreclosure									9,300,000,000
Loss Contingency, Loss in Period										19,000,000
Aml Bsa Related Litigation [Member]
Loss Contingencies [Line Items]
Litigation Settlement Agreement, Compliance Period			5 years
Litigation Settlement Agreement, Compliance Period, Two			2 years
Levin, Jura and Hanes [Member]
Loss Contingencies [Line Items]
Loss Contingency, Pending Claims, Number															3
DeKalb County [Member]
Loss Contingencies [Line Items]
Number of Counties, Plaintiffs																3
Number of Counties in Area																5
Hsbc Securities [Member] | Mortgage Securitization Activity Related Litigation [Member]
Loss Contingencies [Line Items]
Mortgage Securitization Loan Purchase And Sold											24,000,000,000
Mortgage Securitization Outstanding Loan Purchase And Sold			6,500,000,000									5,700,000,000
FHLB Topeka, Royal Park Investments SA/NV, Phoenix Light SF Limited [Member] | Blackrock and PIMCO Funds [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value												2,760,000,000
Number of Identified Trusts												20
Hsbc North America [Member] | Foreclosure Practices [Member]
Loss Contingencies [Line Items]
Loss Contingency, Cash Payment Into Fund									96,000,000
Loss Contingency, Loss in Period										104,000,000
Hsbc North America [Member] | Aml Bsa Related Litigation [Member]
Loss Contingencies [Line Items]
Loss Contingency, Settlement Agreement, Term of Contract			5 years
Legal settlement, amount paid													1,921,000,000
HSBC Bank USA [Member] | Foreclosure Practices [Member]
Loss Contingencies [Line Items]
Number Of States Under Different Departments																	49
Number Of Largest Domestic Mortgage Servicers																	5
Product Liability Accrual, Component Amount																		38,000,000
HSBC Bank USA [Member] | Aml Bsa Related Litigation [Member]
Loss Contingencies [Line Items]
Legal settlement, amount paid													1,381,000,000
Subsequent Event [Member] | Alfredo Villoldo, et al. v. HSBC Bank USA, NA, et. al. [Member]
Loss Contingencies [Line Items]
Loss Contingency, Damages Sought, Value														30,000,000
Legal settlement amount														$ 2,900,000,000