Mortgage Banking Activities, Noninterest Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Servicing fees:
Contractually specified servicing fees	$ 4,626	$ 4,611	$ 4,566
Late charges	257	298	360
Ancillary fees	342	354	434
Unreimbursed direct servicing costs	(1,234)	(1,119)	(763)
Net servicing fees	3,991	4,144	4,597
Changes in fair value of MSRs carried at fair value:
Net changes in valuation model inputs or assumptions	(2,893)	(3,680)	(2,957)
Other changes in fair value	(3,061)	(2,141)	(2,554)
Total changes in fair value of MSRs measured at fair value	(5,954)	(5,821)	(5,511)
Amortization	(233)	(264)	(228)
Provision for mortgage servicing rights in excess of fair value	0	(34)	(3)
Net derivative gains from economic hedges	3,574	5,241	4,485
Total servicing income, net	1,378	3,266	3,340
Net gains on mortgage loan origination/sales activities	10,260	4,566	6,397
Total mortgage banking noninterest income	11,638	7,832	9,737
Market related valuation changes to MSRs, net of hedge results	$ 681	$ 1,561	$ 1,528

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 50

-Section 50

-Paragraph 4

-Subparagraph (a)(4)

-URI http://asc.fasb.org/extlink&oid=7882072&loc=d3e122739-111746

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph g(1)(d)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.