Goodwill and Other Intangible Assets (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Intangible Assets By Major Class [Line Items]
Goodwill	$ 48,175	$ 48,188	$ 48,854	$ 48,357
Mortgage servicing rights	7,614	7,223	13,649	15,531
Other intangible assets:
Other intangible assets	2,235	3,207	4,039
Purchased Credit Card Relationships [Member]
Other intangible assets:
Other intangible assets	295	602	897
Other credit card- related intangibles [Member]
Other intangible assets:
Other intangible assets	229	488	593
Core Deposits [Member]
Other intangible assets:
Other intangible assets	355	594	879
Other intangibles [Member]
Other intangible assets:
Other intangible assets	$ 1,356	$ 1,523	$ 1,670