Contingencies, Commitments and Guarantees (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Loss Contingencies [Line Items]
2013	$ 474
2014	422
2015	377
2016	296
2017	224
Thereafter	1,035
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
Gross rental payments 2013	278
Gross rental payments 2014	213
Gross rental payments 2015	183
Gross rental payments 2016	155
Gross rental payments 2017	131
Gross rental payments thereafter	886
Sublease Income [Member]
Loss Contingencies [Line Items]
2013	25
2014	18
2015	16
2016	16
2017	15
Thereafter	$ 81

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- Definition

Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph 16

-Subparagraph b(i)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

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- Definition

Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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- Definition

Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

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-Name Accounting Standards Codification

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- Definition

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

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- Definition

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

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Future rental payments receivable within the third 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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