The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 48

-Paragraph 21

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

Name:	us-gaap_UnrecognizedTaxBenefits
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Income Taxes (Details Textuals) (USD $) In Millions	1 Months Ended		3 Months Ended		9 Months Ended		12 Months Ended
Income Taxes (Details Textuals) (USD $) In Millions	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2012
Income Taxes (Textuals) [Abstract]
Gross unrecognized tax benefits	$ 935	$ 965	$ 935		$ 935
Gross recognized tax benefits	830	859	830		830
Incremental tax liability asserted by IRS	154	525
Income tax benefits related to interest			4	3
Interest Expense Related To Income Taxes					12	10
Accrued Interest And Penalties Gross	303	285	303		303
Potential reduction in unrecognized tax benefits over next 12 months as a result of concluding certain matters							$ 30