Loans - Contractual Maturities (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	$ 20,109
2015	6,631
2016	6,179
2017	6,125
2018	10,662
Thereafter	17,989
Total loans	67,695		63,258	51,867
Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	48,494		44,150
Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	19,201		19,108
Construction and Other Real Estate [Member] | Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	3,233
2015	870
2016	1,019
2017	1,030
2018	1,890
Thereafter	992
Total loans	9,034		8,457	7,860
Business Banking And Middle Markets Enterprises [Member] | Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	5,170
2015	1,392
2016	1,630
2017	1,647
2018	3,022
Thereafter	1,585
Total loans	14,446		12,608	10,225
Global Banking [Member] | Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	7,739
2015	2,084
2016	2,440
2017	2,466
2018	4,523
Thereafter	2,373
Total loans	21,625		20,009	12,658
Other Commercial [Member] | Commercial Loan [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	1,213
2015	327
2016	382
2017	386
2018	709
Thereafter	372
Total loans	3,389		3,076	2,906
Home Equity Mortgages [Member] | Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	838
2015	444
2016	272
2017	168
2018	105
Thereafter	184
Total loans	2,011		2,324	2,563
Residential Mortgage [Member] | Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	1,645	[1]
2015	432	[1]
2016	427	[1]
2017	426	[1]
2018	413	[1]
Thereafter	12,483	[1]
Total loans	15,826	[1]	15,371	14,113
Credit Cards [Member] | Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	0	[2]
2015	854	[2]
2016	0	[2]
2017	0	[2]
2018	0	[2]
Thereafter	0	[2]
Total loans	854	[2]	815	828
Other consumer | Consumer Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2014	271
2015	228
2016	9
2017	2
2018	0
Thereafter	0
Total loans	$ 510		$ 598	$ 714

[1] Home equity mortgages maturities reflect estimates based on historical payment patterns.

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