Business Segment Reporting (Detail) (USD $) In Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010		Sep. 30, 2011		Sep. 30, 2010
Average total assets	$ 172,076		$ 171,999		$ 171,886		$ 171,569
Average total liabilities	152,076		148,908		151,025		148,986
Average total equity	20,000		23,091		20,861		22,583
Net, interest income	1,263		1,238		3,771		3,587
FTE adjustment	30		28		84		89
Net interest income (FTE)	1,293	[1]	1,266	[1]	3,855	[1]	3,676	[1]
Provision for credit losses	347	[2]	615	[2]	1,186	[2]	2,138	[2]
Net interest income/(loss) after provision for credit losses	946		651		2,669		1,538
Noninterest income	903		1,047		2,698		2,697
Noninterest expense	1,560		1,499		4,567		4,362
Income/(loss) before provision/(benefit) for income taxes	289		199		800		(127)
Provision/(benefit) for income taxes	75	[3]	42	[3]	220	[3]	(141)	[3]
Net income/(loss) including income attributable to noncontrolling interest	214		157		580		14
Net income attributable to noncontrolling interest	(1)		4		7		9
Net income/(loss)	215		153		573		5
Retail Banking
Average total assets	40,821		39,105		40,752		38,856
Average total liabilities	76,820		74,945		76,582		74,411
Average total equity	0		0		0		0
Net, interest income	640		630		1,897		1,870
FTE adjustment	0		0		0		0
Net interest income (FTE)	640	[1]	630	[1]	1,897	[1]	1,870	[1]
Provision for credit losses	181	[2]	229	[2]	593	[2]	765	[2]
Net interest income/(loss) after provision for credit losses	459		401		1,304		1,105
Noninterest income	286		278		830		857
Noninterest expense	654		623		1,936		1,850
Income/(loss) before provision/(benefit) for income taxes	91		56		198		112
Provision/(benefit) for income taxes	33	[3]	20	[3]	72	[3]	39	[3]
Net income/(loss) including income attributable to noncontrolling interest	58		36		126		73
Net income attributable to noncontrolling interest	0		0		0		0
Net income/(loss)	58		36		126		73
Diversified Commercial Banking
Average total assets	25,242		24,633		25,113		25,039
Average total liabilities	20,541		19,159		20,459		19,864
Average total equity	0		0		0		0
Net, interest income	159		142		456		408
FTE adjustment	26		26		76		80
Net interest income (FTE)	185	[1]	168	[1]	532	[1]	488	[1]
Provision for credit losses	11	[2]	23	[2]	49	[2]	88	[2]
Net interest income/(loss) after provision for credit losses	174		145		483		400
Noninterest income	67		62		191		173
Noninterest expense	123		107		358		335
Income/(loss) before provision/(benefit) for income taxes	118		100		316		238
Provision/(benefit) for income taxes	42	[3]	37	[3]	114	[3]	87	[3]
Net income/(loss) including income attributable to noncontrolling interest	76		63		202		151
Net income attributable to noncontrolling interest	0		0		0		0
Net income/(loss)	76		63		202		151
Commercial Real Estate
Average total assets	7,557		10,395		8,230		11,171
Average total liabilities	1,535		1,467		1,479		1,667
Average total equity	0		0		0		0
Net, interest income	34		38		105		124
FTE adjustment	0		0		1		0
Net interest income (FTE)	34	[1]	38	[1]	106	[1]	124	[1]
Provision for credit losses	133	[2]	156	[2]	353	[2]	344	[2]
Net interest income/(loss) after provision for credit losses	(99)		(118)		(247)		(220)
Noninterest income	25		21		73		61
Noninterest expense	100		120		316		324
Income/(loss) before provision/(benefit) for income taxes	(174)		(217)		(490)		(483)
Provision/(benefit) for income taxes	(85)	[3]	(103)	[3]	(242)	[3]	(242)	[3]
Net income/(loss) including income attributable to noncontrolling interest	(89)		(114)		(248)		(241)
Net income attributable to noncontrolling interest	0		0		0		0
Net income/(loss)	(89)		(114)		(248)		(241)
Corporate and Investment Banking
Average total assets	23,990		20,900		22,651		19,597
Average total liabilities	17,857		16,478		17,620		15,272
Average total equity	0		0		0		0
Net, interest income	126		98		360		272
FTE adjustment	1		0		2		1
Net interest income (FTE)	127	[1]	98	[1]	362	[1]	273	[1]
Provision for credit losses	(3)	[2]	0	[2]	(1)	[2]	37	[2]
Net interest income/(loss) after provision for credit losses	130		98		363		236
Noninterest income	109		196		477		449
Noninterest expense	139		121		433		352
Income/(loss) before provision/(benefit) for income taxes	100		173		407		333
Provision/(benefit) for income taxes	36	[3]	64	[3]	149	[3]	123	[3]
Net income/(loss) including income attributable to noncontrolling interest	64		109		258		210
Net income attributable to noncontrolling interest	0		0		0		0
Net income/(loss)	64		109		258		210
Mortgage
Average total assets	33,159		34,556		33,681		34,627
Average total liabilities	3,705		4,135		3,487		3,581
Average total equity	0		0		0		0
Net, interest income	121		123		362		331
FTE adjustment	0		0		0		0
Net interest income (FTE)	121	[1]	123	[1]	362	[1]	331	[1]
Provision for credit losses	144	[2]	265	[2]	520	[2]	956	[2]
Net interest income/(loss) after provision for credit losses	(23)		(142)		(158)		(625)
Noninterest income	115		272		271		397
Noninterest expense	318		296		847		812
Income/(loss) before provision/(benefit) for income taxes	(226)		(166)		(734)		(1,040)
Provision/(benefit) for income taxes	(88)	[3]	(63)	[3]	(283)	[3]	(395)	[3]
Net income/(loss) including income attributable to noncontrolling interest	(138)		(103)		(451)		(645)
Net income attributable to noncontrolling interest	0		0		0		1
Net income/(loss)	(138)		(103)		(451)		(646)
Wealth and Investment Management
Average total assets	8,370		8,941		8,489		8,974
Average total liabilities	12,812		11,723		12,658		11,449
Average total equity	0		0		0		0
Net, interest income	105		97		305		280
FTE adjustment	0		0		0		0
Net interest income (FTE)	105	[1]	97	[1]	305	[1]	280	[1]
Provision for credit losses	26	[2]	15	[2]	54	[2]	44	[2]
Net interest income/(loss) after provision for credit losses	79		82		251		236
Noninterest income	202		196		624		578
Noninterest expense	235		233		710		672
Income/(loss) before provision/(benefit) for income taxes	46		45		165		142
Provision/(benefit) for income taxes	19	[3]	16	[3]	61	[3]	52	[3]
Net income/(loss) including income attributable to noncontrolling interest	27		29		104		90
Net income attributable to noncontrolling interest	(4)		1		0		1
Net income/(loss)	31		28		104		89
Corporate Other and Treasury
Average total assets	31,389		33,321		31,348		32,557
Average total liabilities	16,235		18,742		16,058		20,040
Average total equity	0		0		0		0
Net, interest income	132		117		379		350
FTE adjustment	1		2		5		8
Net interest income (FTE)	133	[1]	119	[1]	384	[1]	358	[1]
Provision for credit losses	0	[2]	0	[2]	(1)	[2]	0	[2]
Net interest income/(loss) after provision for credit losses	133		119		385		358
Noninterest income	103		24		254		193
Noninterest expense	(2)		1		(11)		29
Income/(loss) before provision/(benefit) for income taxes	238		142		650		522
Provision/(benefit) for income taxes	80	[3]	44	[3]	236	[3]	170	[3]
Net income/(loss) including income attributable to noncontrolling interest	158		98		414		352
Net income attributable to noncontrolling interest	2		2		7		7
Net income/(loss)	156		96		407		345
Reconciling Items
Average total assets	1,548		148		1,622		748
Average total liabilities	2,571		2,259		2,682		2,702
Average total equity	20,000		23,091		20,861		22,583
Net, interest income	(54)		(7)		(93)		(48)
FTE adjustment	2		0		0		0
Net interest income (FTE)	(52)	[1]	(7)	[1]	(93)	[1]	(48)	[1]
Provision for credit losses	(145)	[2]	(73)	[2]	(381)	[2]	(96)	[2]
Net interest income/(loss) after provision for credit losses	93		66		288		48
Noninterest income	(4)		(2)		(22)		(11)
Noninterest expense	(7)		(2)		(22)		(12)
Income/(loss) before provision/(benefit) for income taxes	96		66		288		49
Provision/(benefit) for income taxes	38	[3]	27	[3]	113	[3]	25	[3]
Net income/(loss) including income attributable to noncontrolling interest	58		39		175		24
Net income attributable to noncontrolling interest	1		1		0		0
Net income/(loss)	$ 57		$ 38		$ 175		$ 24

[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.