Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2011	Dec. 31, 2010
Amortized intangible assets:
Gross carrying value	$ 18,260	$ 20,620
Accumulated amortization	(9,402)	(10,262)
Net carrying Value	8,858	10,358
Unamortized intangible assets:
MSRs (carried at fair value)	10,956	12,603
Goodwill	25,637	25,115	25,038	24,770
Trademark	14	14
Amortized MSRs [Member]
Amortized intangible assets:
Gross carrying value	2,240	2,383
Accumulated amortization	(1,096)	(975)
Net carrying Value	1,144	1,408
Core deposit intangibles [Member]
Amortized intangible assets:
Gross carrying value	12,836	15,079
Accumulated amortization	(6,572)	(7,768)
Net carrying Value	6,264	7,311
Customer Relationships And Other [Member]
Amortized intangible assets:
Gross carrying value	3,184	3,158
Accumulated amortization	(1,734)	(1,519)
Net carrying Value	$ 1,450	$ 1,639