Contingencies, Commitments and Guarantees (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Loss Contingencies [Line Items]
2012	$ 425
2013	386
2014	332
2015	283
2016	223
Thereafter	921
Operating Leases, Future Minimum Payments Due [Abstract]
Gross rental payments 2012	337
Gross rental payments 2013	279
Gross rental payments 2014	202
Gross rental payments 2015	172
Gross rental payments 2016	145
Gross rental payments thereafter	917
Sublease Income [Member]
Loss Contingencies [Line Items]
2012	17
2013	20
2014	12
2015	12
2016	12
Thereafter	$ 74

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within one year of the balance sheet date relating to leases defined as operating.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fourth year of the balance sheet date relating to leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the second year of the balance sheet date relating to leases defined as operating.

+ References

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due after the fifth year from the balance sheet date on leases defined as operating.

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+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph b(ii)

-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.

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-Name Accounting Standards Codification

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Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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