Loans - Impaired Commercial Loans Considered as TDR Loans (Parenthetical) (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012
Financing Receivable, Impaired [Line Items]
TDR Loans	$ 1,370	[1],[2],[3]	$ 1,434	[1],[2],[3]
Commercial Loan [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	165		250
TDR Loans	389	[1],[2]	460	[1],[2]
Unpaid principal balance of impaired commercial loans	641		806
Commercial Loan [Member] | Construction and Other Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	122		192
TDR Loans	292	[1],[2]	343	[1],[2]
Unpaid principal balance of impaired commercial loans	380		552
Commercial Loan [Member] | Business and Corporate Banking [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	28		57
TDR Loans	21	[1],[2]	86	[1],[2]
Unpaid principal balance of impaired commercial loans	91		157
Commercial Loan [Member] | Global Banking [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	14		0
TDR Loans	51	[1],[2]	0	[1],[2]
Unpaid principal balance of impaired commercial loans	123		18
Commercial Loan [Member] | Other Commercial [Member]
Financing Receivable, Impaired [Line Items]
Amount with Impairment Reserves	1		1
TDR Loans	25	[1],[2]	31	[1],[2]
Unpaid principal balance of impaired commercial loans	$ 47		$ 79

[1] The TDR Loan balances included in the table above reflect the current carrying amount of TDR Loans and includes all basis adjustments on the loan, such as unearned income, unamortized deferred fees and costs on originated loans, partial charge-offs and premiums or discounts on purchased loans. The following table reflects the unpaid principal balance of TDR Loans:At December 31,2013 2012 (in millions)Commercial loans: Construction and other real estate$309 $398Business and corporate banking60 137Global banking51 —Other commercial28 34Total commercial448 569Consumer loans: Residential mortgages1,153 1,118Credit cards8 14Total consumer1,161 1,132Total$1,609 $1,701

[2] TDR Loans are considered to be impaired loans. For consumer loans, all such loans are considered impaired loans regardless of accrual status. For commercial loans, impaired loans include other loans in addition to TDR Loans which totaled $92 million and $237 million at December 31, 2013 and 2012, respectively.

[3] Includes $458 million and $519 million at December 31, 2013 and 2012, respectively, of loans which are classified as nonaccrual.