Loans - Components of Loans (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2014		Dec. 31, 2013		Jun. 30, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 72,198		$ 67,695		$ 66,705
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial	53,033		48,494
Total loans	53,033		48,494
Commercial Loan [Member] | Construction and Other Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial	9,682		9,034
Total loans	9,682		9,034		8,529
Commercial Loan [Member] | Business and Corporate Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial	15,956		14,446
Total loans	15,956		14,446		12,391
Commercial Loan [Member] | Global Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial	24,268	[1]	21,625	[1]
Total loans	24,268		21,625		23,339
Commercial Loan [Member] | Other Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total commercial	3,127		3,389
Total loans	3,127		3,389		3,005
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer	19,165		19,201
Total loans	19,165		19,201
Consumer Loans [Member] | Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer	16,097		15,826
Total loans	16,097		15,826		15,837
Consumer Loans [Member] | Home Equity Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer	1,914		2,011
Total loans	1,914		2,011		2,172
Consumer Loans [Member] | Credit Cards [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer	681		854
Total loans	681		854		858
Consumer Loans [Member] | Other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total consumer	473		510
Total loans	$ 473		$ 510		$ 574

[1] Represents large multinational firms including globally focused U.S. corporate and financial institutions and U.S. dollar lending to multinational banking customers managed by HSBC on a global basis. Also includes loans to HSBC affiliates which totaled $5,080 million and $5,328 million at June 30, 2014 and December 31, 2013, respectively. See Note 13, "Related Party Transactions" for additional information regarding loans to HSBC affiliates.