Business Segments - Summary on Reconciliation of Results Under Ifrs to Us Gaap (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Operating Statistics [Line Items]
Total Assets	$ (49,879)					$ (67,543)					$ (49,879)		$ (67,543)		$ (81,772)
US GAAP Based, Net interest income	526		492	518	505	526		510	535	587	2,041	[1]	2,158	[1]	2,434
US GAAP Based, Other operating income	267		432	566	592	303		408	879	383	1,857		1,973		2,325
US GAAP Based, Total operating income											3,898		4,131		4,759
Provision for credit losses	51		54	67	21	120		84	89	0	193		293		258
US GAAP Based, Operating income, net											3,705		3,838		4,501
US GAAP Based, Operating expenses	1,540		855	788	789	681		1,628	1,567	872	3,972	[2]	4,748	[2]	3,819
Income (loss) from continuing operations before income tax expense	(798)		15	229	287	28		(794)	(242)	98	(267)		(910)		682
Total assets	185,487	[3]				191,446	[3]				185,487	[3]	191,446	[3]
US GAAP Based, Total loans, net	67,089					62,611					67,089		62,611		51,124
US GAAP Based, Goodwill	1,612					2,228					1,612		2,228		2,228
US GAAP Based, Total deposits	112,608					117,671					112,608		117,671		139,729
Adjustments Or Reconciling Items [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											(13)	[1]	(15)	[1]	(23)
IFRS Based, Other operating income											13		15		23
IFRS Based, Total operating income											0		0		0
IFRS Loan Impairment charges											0		0		0
IFRS Based, Operating income, net											0		0		0
IFRS Based Operating expenses											0	[2]	0	[2]	0
IFRS Based, Profit before income tax expense											0		0		0
Total Assets	0					0					0		0		0
IFRS Based, Total loans, net	0					0					0		0		0
IFRS Based, Goodwill	0					0					0		0		0
IFRS Based, Total deposits	0					0					0		0		0
Aggregate [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											2,101	[1]	2,259	[1]	2,312
IFRS Based, Other operating income											1,849		1,862		2,400
IFRS Based, Total operating income											3,950		4,121		4,712
IFRS Loan Impairment charges											175		204		228
IFRS Based, Operating income, net											3,775		3,917		4,484
IFRS Based Operating expenses											3,702	[2]	4,626	[2]	3,620
IFRS Based, Profit before income tax expense											73		(709)		864
Total Assets	232,359					258,895					232,359		258,895		267,149
IFRS Based, Total loans, net	65,147					62,562					65,147		62,562		59,121
IFRS Based, Goodwill	1,264					1,744					1,264		1,744		1,744
IFRS Based, Total deposits	110,009					113,257					110,009		113,257		116,866
Ifrs Adjustments [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											(76)	[1],[4]	(123)	[1],[4]	(41)
IFRS Based, Other operating income											22	[4]	43	[4]	(20)
IFRS Based, Total operating income											(54)	[4]	(80)	[4]	(61)
IFRS Loan Impairment charges											0	[4]	73	[4]	(3)
IFRS Based, Operating income, net											(54)	[4]	(153)	[4]	(58)
IFRS Based Operating expenses											286	[2],[4]	48	[2],[4]	124
IFRS Based, Profit before income tax expense											(340)	[4]	(201)	[4]	(182)
Total Assets	(49,879)	[4]				(67,543)	[4]				(49,879)	[4]	(67,543)	[4]	(80,526)
IFRS Based, Total loans, net	1,503	[4]				3,495	[4]				1,503	[4]	3,495	[4]	(4,636)
IFRS Based, Goodwill	348	[4]				484	[4]				348	[4]	484	[4]	484
IFRS Based, Total deposits	(3,869)	[4]				(5,122)	[4]				(3,869)	[4]	(5,122)	[4]	(4,788)
Ifrs Reclassifications [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											16	[1],[5]	22	[1],[5]	163
IFRS Based, Other operating income											(14)	[5]	68	[5]	(55)
IFRS Based, Total operating income											2	[5]	90	[5]	108
IFRS Loan Impairment charges											18	[5]	16	[5]	33
IFRS Based, Operating income, net											(16)	[5]	74	[5]	75
IFRS Based Operating expenses											(16)	[2],[5]	74	[2],[5]	75
IFRS Based, Profit before income tax expense											0	[5]	0	[5]	0
Total Assets	3,007	[5]				94	[5]				3,007	[5]	94	[5]	(115)
IFRS Based, Total loans, net	439	[5]				(3,446)	[5]				439	[5]	(3,446)	[5]	(3,361)
IFRS Based, Goodwill	0	[5]				0	[5]				0	[5]	0	[5]	0
IFRS Based, Total deposits	6,468	[5]				9,536	[5]				6,468	[5]	9,536	[5]	27,651
Continuing Operations [Member]
Operating Statistics [Line Items]
Total assets															186,508
RBWM [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											842	[1]	854	[1]	1,023
IFRS Based, Other operating income											347		555		409
IFRS Based, Total operating income											1,189		1,409		1,432
IFRS Loan Impairment charges											129		204		247
IFRS Based, Operating income, net											1,060		1,205		1,185
IFRS Based Operating expenses											1,206	[2]	1,301	[2]	1,653
IFRS Based, Profit before income tax expense											(146)		(96)		(468)
Total Assets	19,267					22,789					19,267		22,789		28,017
IFRS Based, Total loans, net	16,233					16,422					16,233		16,422		16,233
IFRS Based, Goodwill	581					581					581		581		581
IFRS Based, Total deposits	30,220					35,406					30,220		35,406		36,837
CMB [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											706	[1]	673	[1]	728
IFRS Based, Other operating income											293		539		322
IFRS Based, Total operating income											999		1,212		1,050
IFRS Loan Impairment charges											45		4		6
IFRS Based, Operating income, net											954		1,208		1,044
IFRS Based Operating expenses											680	[2]	631	[2]	652
IFRS Based, Profit before income tax expense											274		577		392
Total Assets	23,427					23,585					23,427		23,585		21,148
IFRS Based, Total loans, net	22,254					19,754					22,254		19,754		16,782
IFRS Based, Goodwill	358					358					358		358		358
IFRS Based, Total deposits	21,601					21,759					21,601		21,759		21,799
GBM [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											423	[1]	606	[1]	504
IFRS Based, Other operating income											1,165		916		969
IFRS Based, Total operating income											1,588		1,522		1,473
IFRS Loan Impairment charges											(4)		(1)		5
IFRS Based, Operating income, net											1,592		1,523		1,468
IFRS Based Operating expenses											1,464	[2]	997	[2]	986
IFRS Based, Profit before income tax expense											128		526		482
Total Assets	180,559					203,680					180,559		203,680		210,846
IFRS Based, Total loans, net	20,454					20,679					20,454		20,679		21,390
IFRS Based, Goodwill	0					480					0		480		480
IFRS Based, Total deposits	46,152					43,951					46,152		43,951		45,061
PB [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											189	[1]	184	[1]	180
IFRS Based, Other operating income											109		106		184
IFRS Based, Total operating income											298		290		364
IFRS Loan Impairment charges											5		(3)		(30)
IFRS Based, Operating income, net											293		293		394
IFRS Based Operating expenses											254	[2]	232	[2]	261
IFRS Based, Profit before income tax expense											39		61		133
Total Assets	8,340					8,208					8,340		8,208		6,525
IFRS Based, Total loans, net	6,206					5,707					6,206		5,707		4,716
IFRS Based, Goodwill	325					325					325		325		325
IFRS Based, Total deposits	12,036					12,141					12,036		12,141		13,169
Other [Member]
Operating Statistics [Line Items]
IFRS Based, Net Interest Income											(46)	[1]	(43)	[1]	(100)
IFRS Based, Other operating income											(78)		(269)		493
IFRS Based, Total operating income											(124)		(312)		393
IFRS Loan Impairment charges											0		0		0
IFRS Based, Operating income, net											(124)		(312)		393
IFRS Based Operating expenses											98	[2]	1,465	[2]	68
IFRS Based, Profit before income tax expense											(222)		(1,777)		325
Total Assets	766					633					766		633		613
IFRS Based, Total loans, net	0					0					0		0		0
IFRS Based, Goodwill	0					0					0		0		0
IFRS Based, Total deposits	$ 0					$ 0					$ 0		$ 0		$ 0

[1] Net interest income of each segment represents the difference between actual interest earned on assets and interest paid on liabilities of the segment adjusted for a funding charge or credit. Segments are charged a cost to fund assets (e.g. customer loans) and receive a funding credit for funds provided (e.g. customer deposits) based on equivalent market rates. The objective of these charges/credits is to transfer interest rate risk from the segments to one centralized unit in Treasury and more appropriately reflect the profitability of segments.

[2] Expenses for the segments include fully apportioned corporate overhead expenses.

[3] The following table summarizes assets and liabilities related to our consolidated variable interest entities (“VIEs”) as of December 31, 2013 and December 31, 2012 which are consolidated on our balance sheet. Assets and liabilities exclude intercompany balances that eliminate in consolidation. Assets: Interest bearing deposits with banks, $5 million and $0 million, Securities held-to-maturity, $200 million and $0 million Other assets $502 million and $533 million. Total assets $707 million and $533 million respectively. Liabilities: Long-term debt $92 million and $92 million, Interest, taxes and other liabilities $93 million and $152 million. Total liabilities $185 million and $244 million, respectively.

[4] Represents adjustments associated with differences between IFRSs and U.S. GAAP bases of accounting. These adjustments, which are more fully described above, consist of the following:

[5] Represents differences in financial statement presentation between IFRSs and U.S. GAAP.