Fair Value Election and Measurement Netting of Financial Instruments (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013		Dec. 31, 2012
Netting of Financial Instruments [Line Items]
Carrying Value of Securities Purchased under Agreements to Resell and Deposits Paid for Securities Borrowed	$ 1,154		$ 1,072
Securities Borrowed or Purchased Under Agreements to Resell, Amount Offset Against Collateral	0		0
Federal Funds Sold and Securities Purchased under Agreements to Resell	1,154	[1]	1,072	[2],[3]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	1,737		1,989
Derivative Liability, Fair Value, Amount Offset Against Collateral	6,236		7,102
Derivative Asset, Fair Value, Amount Offset Against Collateral	5,737		6,573
Securities Borrowed or Purchased under Agreements to Resell	1,147		1,069
Securities Borrowed or Purchased Under Agreements to Resell, Amount Not Offset Against Collateral	7		3
Securities Purchased under Agreements to Resell	1,854		1,574
Securities Sold Under Agreements to Repurchase, Amount Not Offset Against Collateral	0		0
Derivative Liability, Fair Value, Gross Liability	6,795		7,514
Derivative Liabilities	559	[4]	412	[5]
Financial Instruments, Owned and Pledged as Collateral, at Fair Value	1,884		1,611
Derivative asset positions	7,568		8,656
Derivative Assets	1,831	[6]	2,083	[7]
Collateral Held by The Company Against Derivative Asset Positions	94		94
Financial Assets, Fair Value, Gross Assets	8,722		9,728
Financial Assets, Amount Offset Against Collateral	5,737		6,573
Financial Assets, Net of Amount Offset	2,985		3,155
Collateralized Agreements	1,241		1,163
Financial Assets, Amount Not Offset Against Collateral	1,744		1,992
Carrying Value of Securities Sold under Repurchase Agreements and Deposits Received for Securities Loaned	1,854		1,574
Securities Sold Under Agreements to Repurchase, Amount Offset Against Collateral	0		0
Federal Funds Sold			29
Securities Sold under Agreements to Repurchase	1,854	[1]	1,574	[2]
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	529		375
Liabilities, Fair Value Disclosure	8,649		9,088
Financial Liabilities, Amount Offset Against Collateral	6,236		7,102
Financial Liabilities, Net of Amount Offset	2,413		1,986
Financial Liabilities, Amount Not Offset Against Collateral	529		375
Fair Value, Measurements, Recurring [Member]
Netting of Financial Instruments [Line Items]
Trading Liabilities, Fair Value Disclosure	(1,348)		(1,161)
Trading Account Assets, Fair Value Disclosure	(6,250)		(6,049)
Other Assets, Fair Value Disclosure	120	[8]	178	[8]
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Netting of Financial Instruments [Line Items]
Other Liabilities, Fair Value Disclosure	28	[8],[9]	15	[8],[9]
Derivatives Subject to Master Netting Arrangement or Similar Arrangement [Member]
Netting of Financial Instruments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	1,532		1,674
Derivative Liability, Fair Value, Amount Offset Against Collateral	5,888		6,802
Derivative Asset, Fair Value, Amount Offset Against Collateral	5,389		6,273
Derivative Liability, Fair Value, Gross Liability	6,263		7,051
Derivative Liabilities	375		249
Financial Instruments, Owned and Pledged as Collateral, at Fair Value	30		37
Derivative asset positions	7,015		8,041
Derivative Assets	1,626		1,768
Collateral Held by The Company Against Derivative Asset Positions	94		94
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	345		212
Exchange Traded/Cleared [Member]
Netting of Financial Instruments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	105		183
Derivative Liability, Fair Value, Amount Offset Against Collateral	348		300
Derivative Asset, Fair Value, Amount Offset Against Collateral	348		300
Derivative Liability, Fair Value, Gross Liability	348		300
Derivative Liabilities	0		0
Financial Instruments, Owned and Pledged as Collateral, at Fair Value	0		0
Derivative asset positions	453		483
Derivative Assets	105		183
Collateral Held by The Company Against Derivative Asset Positions	0		0
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	0		0
Derivatives Not Subject to Master Netting Arrangement or Similar Arrangement [Member] [Member]
Netting of Financial Instruments [Line Items]
Derivative Asset, Fair Value, Amount Not Offset Against Collateral	100		132
Derivative Liability, Fair Value, Amount Offset Against Collateral	0		0
Derivative Asset, Fair Value, Amount Offset Against Collateral	0		0
Derivative Liability, Fair Value, Gross Liability	184		163
Derivative Liabilities	184		163
Financial Instruments, Owned and Pledged as Collateral, at Fair Value	0		0
Derivative asset positions	100		132
Derivative Assets	100		132
Collateral Held by The Company Against Derivative Asset Positions	0		0
Pledged Financial Instruments, Not Separately Reported, Loans Receivable Pledged as Collateral	184		163
Derivative Financial Instruments, Liabilities [Member]
Netting of Financial Instruments [Line Items]
Financial Instruments, Owned and Pledged as Collateral, at Fair Value	30		37
Netting [Member]
Netting of Financial Instruments [Line Items]
Trading Liabilities, Fair Value Disclosure	(1,300)	[10]	(1,300)	[11]
Trading Account Assets, Fair Value Disclosure	(775)	[10]	(730)	[10]
Trading Account Assets [Member]
Netting of Financial Instruments [Line Items]
Derivative Assets	1,700		1,900
Trading Liabilities [Member]
Netting of Financial Instruments [Line Items]
Derivative Liabilities	$ 531		$ 397

[1] None of the Company's repurchase and reverse repurchase transactions met the right of setoff criteria at March 31, 2013.

[2] None of the Company's repurchase and reverse repurchase transactions met the right of setoff criteria at December 31, 2012.

[3] Excludes $29 million of Fed funds sold which are not subject to a master netting agreement at December 31, 2012.

[4] At March 31, 2013, $531 million, net of $1.3 billion offsetting collateral, is recognized in trading liabilities and $28 million is recognized in other liabilities within the Company's Consolidated Balance Sheets.

[5] At December 31, 2012, $397 million, net of $1.3 billion offsetting collateral, is recognized in trading liabilities and $15 million is recognized in other liabilities within the Company's Consolidated Balance Sheets.

[6] At March 31, 2013, $1.7 billion, net of $775 million offsetting collateral, is recognized in trading assets and $120 million is recognized in other assets within the Company's Consolidated Balance Sheets.

[7] At December 31, 2012, $1.9 billion, net of $730 million offsetting collateral, is recognized in trading assets and $178 million is recognized in other assets within the Company's Consolidated Balance Sheets.

[8] These amounts include IRLCs and derivative financial instruments entered into by the Mortgage line of business to hedge its interest rate risk.

[9] These amounts include the derivative associated with the Company's sale of Visa shares during the year ended December 31, 2009, certain CDS, and contingent consideration obligations related to acquisitions.

[10] Amount represents the cash collateral received from or deposited with derivative counterparties. Amount is offset with derivatives in the Consolidated Balance Sheets at March 31, 2013.

[11] Amount represents the cash collateral received from or deposited with derivative counterparties. Amount is offset with derivatives in the Consolidated Balance Sheets at December 31, 2012.