Reinsurance Arrangements and Guarantees - Additional Information (Detail) (USD $) Share data in Millions, unless otherwise specified	9 Months Ended	12 Months Ended			79 Months Ended		1 Months Ended									3 Months Ended		9 Months Ended									9 Months Ended					1 Months Ended	9 Months Ended	12 Months Ended		9 Months Ended	12 Months Ended
	Sep. 30, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 31, 2008	Sep. 30, 2011	Sep. 13, 2011	May 31, 2009 Derivative Financial Instruments, Liabilities [Member] Visa Interest Not Designated as Hedging Instrument [Member]	Sep. 30, 2011 Derivative Financial Instruments, Liabilities [Member] Not Designated as Hedging Instrument [Member]		Dec. 31, 2010 Derivative Financial Instruments, Liabilities [Member] Not Designated as Hedging Instrument [Member]		Sep. 30, 2011 Derivative Financial Instruments, Liabilities [Member]		Dec. 31, 2010 Derivative Financial Instruments, Liabilities [Member]	Sep. 30, 2011 Upper Limit Mortgage Reinsurance Contracts	Sep. 30, 2011 Mortgage Reinsurance Contracts	Sep. 30, 2010 Mortgage Reinsurance Contracts	Sep. 30, 2011 Mortgage Reinsurance Contracts	Sep. 30, 2010 Mortgage Reinsurance Contracts	Dec. 31, 2010 Mortgage Reinsurance Contracts	Sep. 30, 2011 Standby Letters of Credit	Dec. 31, 2010 Standby Letters of Credit	Sep. 30, 2011 Mortgage Loans and Mortgage Servicing Rights	Dec. 31, 2010 Mortgage Loans and Mortgage Servicing Rights	Sep. 30, 2011 Mortgage Loans and Mortgage Servicing Rights Sales	Dec. 31, 2010 Mortgage Loans and Mortgage Servicing Rights Sales	Sep. 30, 2011 Mortgage Loans and Mortgage Servicing Rights, Repurchase Reserves	Sep. 30, 2010 Mortgage Loans and Mortgage Servicing Rights, Repurchase Reserves	Dec. 31, 2010 Mortgage Loans and Mortgage Servicing Rights, Repurchase Reserves	Sep. 30, 2011 Mortgage Loans and Mortgage Servicing Rights, Repurchase Reserves Non Performing Loans	Dec. 31, 2010 Mortgage Loans and Mortgage Servicing Rights, Repurchase Reserves Non Performing Loans	May 31, 2009 Visa Interest	Sep. 30, 2011 Visa Interest	Dec. 31, 2010 Visa Interest	Dec. 31, 2009 Visa Interest	Sep. 30, 2011 Non-Agency Securities	Dec. 31, 2010 Non-Agency Securities	Dec. 31, 2009 Non-Agency Securities	Dec. 31, 2008 Non-Agency Securities	Sep. 30, 2011 Agency Securities	Dec. 31, 2010 Agency Securities	Sep. 30, 2011 Ginnie Mae	Sep. 30, 2011 Contingent Consideration	Dec. 31, 2010 Contingent Consideration
Mortgage loans were covered by such mortgage reinsurance contracts																$ 8,300,000,000		$ 8,300,000,000
Total loss exposure ceded to the Company																320,000,000		320,000,000
Maximum amount of loss exposure based on funds held in each seperate trust account, including net premiums due to the trust accounts																50,000,000		50,000,000
Maximum amount of loss exposure based on funds held in each separate trust account, reserved for reducing the Company's net remaining loss exposure																41,000,000		41,000,000		148,000,000
Future reported losses															9,000,000
Future cash losses															9,000,000
Premium income, mortgage reinsurance																6,000,000	10,000,000	20,000,000	30,000,000
Provision for losses, mortgage reinsurance																5,000,000	7,000,000	18,000,000	25,000,000
Maximum potential amount obligation																					5,500,000,000	6,400,000,000																					11,000,000	5,000,000
Fair value of contingent payments						5,000,000																																					10,000,000	3,000,000
Guarantee obligations, carrying value																					106,000,000	109,000,000	282,000,000	265,000,000	7,000,000	6,000,000
Loans sold from January 1, 2005 to September 30, 2011	239,800,000,000				239,800,000,000																															30,300,000,000				184,500,000,000		25,000,000,000
Repurchase request volume	1,101,000,000	1,100,000,000	1,100,000,000	557,000,000	4,600,000,000																															47,000,000	55,000,000	99,000,000	148,000,000
Unpaid principal balance of loans related to unresolved requests previously received from investors	490,000,000	293,000,000			490,000,000																															28,000,000	29,000,000			462,000,000	264,000,000
Repurchased or otherwise settled mortgages																											488,000,000	512,000,000
Repurchased mortgage loans																											199,000,000		153,000,000	100,000,000	86,000,000
Amount funded by Visa into an escrow account to fund judgments and settlements relating to litigation																																	6,500,000,000
Shares of Class B Visa Inc. common stock sold to another financial institution, shares							3.2
Shares of Class B Visa Inc. common stock sold to another financial institution, value																																112,000,000
Shares of Class B Visa Inc. common stock sold to another financial institution, recognized a gain																																112,000,000
Payments to derivative counterparty																																	7,000,000	17,000,000	10,000,000
Derivative liability positions, fair value								$ 7,250,000,000	[1],[2]	$ 5,019,000,000	[2]	$ 7,396,000,000	[1]	$ 5,174,000,000																			$ 16,000,000	$ 23,000,000
Common stock conversion rate																																0.6296	0.4881

[1] As of July 1, 2011, the Company began offsetting cash collateral paid to and received from derivative counterparties when the derivative contracts are subject to ISDA master netting arrangements and meet the derivatives accounting requirements of ASC 815-10, "Derivatives and Hedging." The effects of offsetting on the Company's Consolidated Balance Sheets as of September 30, 2011 are presented in Note 12, "Fair Value Election and Measurement."

[2] See “Economic Hedging and Trading Activities” in this Note for further discussion.