Guarantee Arrangements and Pledged Assets and Collateral - Additional Information (Detail) (USD $)					36 Months Ended														3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2007 HSBC Securities [Member]	Mar. 31, 2014 Trading Assets [Member]	Dec. 31, 2013 Trading Assets [Member]	Mar. 31, 2014 Available-for-sale Securities [Member]	Dec. 31, 2013 Available-for-sale Securities [Member]	Mar. 31, 2014 Financial standby letters of credit, net of participations [Member]		Dec. 31, 2013 Financial standby letters of credit, net of participations [Member]		Mar. 31, 2014 Performance (non-financial) guarantees [Member]		Dec. 31, 2013 Performance (non-financial) guarantees [Member]		Mar. 31, 2014 Financial Guarantee [Member] Collateralized Securities [Member]	Dec. 31, 2013 Federal National Mortgage Association [Member]	Mar. 31, 2014 Federal Home Loan Mortgage Corporation [Member]	Mar. 31, 2014 Mortgage Securitization Activity Related Litigation [Member] HSBC Securities [Member]	Dec. 31, 2013 Mortgage Securitization Activity Related Litigation [Member] HSBC Securities [Member]
Guarantor Obligations [Line Items]
Outstanding financial standby letters of credit	$ 174,938,000,000	$ 191,349,000,000								$ 5,289,000,000	[1],[2]	$ 5,237,000,000	[1],[2]	$ 3,021,000,000	[1]	$ 3,172,000,000	[1]
Deferred fee on stand by letters of credit	45,000,000	46,000,000
Allowance for credit losses on unfunded standby letters of credit	20,000,000	18,000,000
Settlement with FNMA																			83,000,000	25,000,000
Release of provision																			15,000,000	34,000,000
Outstanding repurchase demands on loans sourced from our legacy broker channel	4,000,000	26,000,000
Repurchase liability for loans	36,000,000	99,000,000	211,000,000	219,000,000
Range of possible losses in excess of recorded repurchase liability, minimum																		0
Range of possible losses in excess of recorded repurchase liability, maximum																		40,000,000
Liquidity facilities	2,303,000,000	2,560,000,000
Securities available-for-sale								18,518,000,000	10,950,000,000
Fair value of collateral received						3,667,000,000	1,296,000,000
Separately reported available-for-sale pledged assets	5,235,000,000	4,187,000,000
Securities sold under agreements to repurchase	1,351,000,000	2,771,000,000
Whole loan securitization					24,000,000,000
Outstanding principal balance on loan																					$ 6,200,000,000	$ 6,500,000,000

[1] For standby letters of credit and liquidity asset purchase agreements, maximum loss represents losses to be recognized assuming the letter of credit and liquidity facilities have been fully drawn and the obligors have defaulted with zero recovery.

[2] Includes $890 million and $865 million issued for the benefit of HSBC affiliates at March 31, 2014 and December 31, 2013, respectively.