Business Segment Reporting (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012		Mar. 31, 2011
Average total assets	$ 176,855		$ 173,066
Average total liabilities	156,599		149,959
Average total equity	20,256		23,107
Net, interest income	1,311		1,249
FTE adjustment	31		28
Net interest income (FTE)	1,342	[1]	1,277	[1]
Provision for credit losses	317	[2]	447	[2]
Net interest income/(loss) after provision for credit losses	1,025		830
Noninterest income	876		883
Noninterest expense	1,541		1,465
Income/(loss) before provision/(benefit) for income taxes	360		248
Provision/(benefit) for income taxes	100	[3]	61	[3]
Net income/(loss) including income attributable to noncontrolling interest	260		187
Net income attributable to noncontrolling interest	10		7
Net income/(loss)	250		180
Consumer Banking
Average total assets	46,105		43,418
Average total liabilities	77,601		76,885
Average total equity	0		0
Net, interest income	634		619
FTE adjustment	0		0
Net interest income (FTE)	634	[1]	619	[1]
Provision for credit losses	155	[2]	202	[2]
Net interest income/(loss) after provision for credit losses	479		417
Noninterest income	323		359
Noninterest expense	707		703
Income/(loss) before provision/(benefit) for income taxes	95		73
Provision/(benefit) for income taxes	34	[3]	27	[3]
Net income/(loss) including income attributable to noncontrolling interest	61		46
Net income attributable to noncontrolling interest	0		0
Net income/(loss)	61		46
Wholesale Banking [Member]
Average total assets	63,358		61,282
Average total liabilities	55,230		53,958
Average total equity	0		0
Net, interest income	429		389
FTE adjustment	29		26
Net interest income (FTE)	458	[1]	415	[1]
Provision for credit losses	101	[2]	146	[2]
Net interest income/(loss) after provision for credit losses	357		269
Noninterest income	379		388
Noninterest expense	515		533
Income/(loss) before provision/(benefit) for income taxes	221		124
Provision/(benefit) for income taxes	59	[3]	23	[3]
Net income/(loss) including income attributable to noncontrolling interest	162		101
Net income attributable to noncontrolling interest	8		5
Net income/(loss)	154		96
Mortgage
Average total assets	35,235		34,537
Average total liabilities	3,828		3,693
Average total equity	0		0
Net, interest income	126		120
FTE adjustment	0		0
Net interest income (FTE)	126	[1]	120	[1]
Provision for credit losses	166	[2]	223	[2]
Net interest income/(loss) after provision for credit losses	(40)		(103)
Noninterest income	157		81
Noninterest expense	334		248
Income/(loss) before provision/(benefit) for income taxes	(217)		(270)
Provision/(benefit) for income taxes	(85)	[3]	(104)	[3]
Net income/(loss) including income attributable to noncontrolling interest	(132)		(166)
Net income attributable to noncontrolling interest	0		0
Net income/(loss)	(132)		(166)
Corporate Other and Treasury
Average total assets	31,250		30,880
Average total liabilities	20,410		15,480
Average total equity	0		0
Net, interest income	126		120
FTE adjustment	1		2
Net interest income (FTE)	127	[1]	122	[1]
Provision for credit losses	0	[2]	0	[2]
Net interest income/(loss) after provision for credit losses	127		122
Noninterest income	21		68
Noninterest expense	(11)		(7)
Income/(loss) before provision/(benefit) for income taxes	159		197
Provision/(benefit) for income taxes	51	[3]	68	[3]
Net income/(loss) including income attributable to noncontrolling interest	108		129
Net income attributable to noncontrolling interest	2		2
Net income/(loss)	106		127
Reconciling Items
Average total assets	907		2,949
Average total liabilities	(470)		(57)
Average total equity	20,256		23,107
Net, interest income	(4)		1
FTE adjustment	1		0
Net interest income (FTE)	(3)	[1]	1	[1]
Provision for credit losses	(105)	[2]	(124)	[2]
Net interest income/(loss) after provision for credit losses	102		125
Noninterest income	(4)		(13)
Noninterest expense	(4)		(12)
Income/(loss) before provision/(benefit) for income taxes	102		124
Provision/(benefit) for income taxes	41	[3]	47	[3]
Net income/(loss) including income attributable to noncontrolling interest	61		77
Net income attributable to noncontrolling interest	0		0
Net income/(loss)	$ 61		$ 77

[1] Net interest income is FTE and is presented on a matched maturity funds transfer price basis for the segments.

[2] Provision for credit losses represents net charge-offs for the segments.

[3] Includes regular income tax provision/(benefit) and taxable-equivalent income adjustment reversal.