Loans - Components of Loans (Details) - USD ($) $ in Millions		Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 73,875		$ 82,917		$ 77,741
Commercial Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		54,216		62,453
Commercial Loans [Member] | Loans Reclassified to Global Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans				4,800		3,900	$ 3,400
Commercial Loans [Member] | Construction and Other Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		10,890		10,000		10,300
Commercial Loans [Member] | Business and Corporate Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[1]	14,080		14,365		13,878
Commercial Loans [Member] | Global Banking [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	[1]	26,755	[2]	34,720	[2]	30,328
Commercial Loans [Member] | Other Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		2,491		3,368		3,581
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		19,659		20,464
Consumer Loans [Member] | Residential Mortgage [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		17,181	[3],[4]	17,758		16,661
Consumer Loans [Member] | Home Equity Mortgages [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		1,408	[5]	1,600		1,784
Consumer Loans [Member] | Credit Cards [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		688	[6]	699		720
Consumer Loans [Member] | Other consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans		$ 382		$ 407		$ 489

[1] During the fourth quarter of 2016, we transferred certain customer relationships from CMB to GB&M as discussed further in Note 22, "Business Segments," in the accompanying consolidated financial statements. As a result, we reclassified $4.8 billion, $3.9 billion and $3.4 billion of loans and $27 million, $24 million and $7 million of allowance for credit losses from business and corporate banking to global banking at December 31, 2015, 2014 and 2013, respectively, to conform with the current year presentation.

[2] Represents large multinational firms including globally focused U.S. corporate and financial institutions, U.S. dollar lending to multinational banking customers managed by HSBC on a global basis and complex large business customers supported by GB&M relationship managers. Also includes loans to HSBC affiliates which totaled $3,274 million and $4,815 million at December 31, 2016 and 2015, respectively. See Note 21, "Related Party Transactions," for additional information regarding loans to HSBC affiliates.

[3] The decrease in nonaccrual loans at December 31, 2016 reflects the impact of transfers of certain residential mortgage loans to held for sale during 2016.

[4] The decrease in past due loans at December 31, 2016 reflects the impact of transfers of certain residential mortgage loans to held for sale during 2016. See Note 7, "Loans Held for Sale" for additional details.

[5] Home equity mortgage maturities reflect estimates based on historical payment patterns.

[6] As credit card receivables do not have stated maturities, the table reflects estimates based on historical payment patterns.