Loans Loans - Net Gains and Losses on Sale (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Gain (Loss) on Sales of Loans, Net	$ 98	$ 84	$ 249	$ 130
Consumer, excluding credit card
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Gain (Loss) on Sales of Loans, Net	112	42	256	74
Credit card
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Gain (Loss) on Sales of Loans, Net	0	6	0	(12)
Wholesale
Net Gains Losses On Loan Sales By Portfolio Segment [Line Items]
Gain (Loss) on Sales of Loans, Net	$ (14)	$ 36	$ (7)	$ 68

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

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 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.13(h))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-04.3(a))

-URI http://asc.fasb.org/extlink&oid=6879464&loc=d3e573970-122913

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