Commitments, Guarantees and Contingent Liabilities (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Commitments, Guarantees and Contingent Liabilities
Total rent expense for all leases	$ 256	$ 256	$ 267
Capital leases, future minimum lease payments
2012	7
2013	8
2014	6
2015	2
2016	2
Thereafter	13
Total	38
Present value of minimum capital lease payments	29
Operating leases, future minimum lease payments
2012	182
2013	138
2014	92
2015	66
2016	47
Thereafter	66
Total	$ 591

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The total of contractually required rental payments on leases meeting the criteria for capitalization.

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Contractually required rental payments on leases meeting the criteria for capitalization, due within one year of the balance sheet date.

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Contractually required rental payments on leases meeting the criteria for capitalization, due within the fifth year from the balance sheet date.

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Contractually required rental payments on leases meeting the criteria for capitalization, due within the third year from the balance sheet date.

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The discounted value of future cash flows under leases meeting the criteria for capitalization.

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Rental expense incurred for leased assets including furniture and equipment which has not been recognized in costs and expenses applicable to sales and revenues; for example, cost of goods sold or other operating costs and expenses.

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The total of future contractually required payments on leases defined as operating.

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

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-Name Statement of Financial Accounting Standard (FAS)

-Number 13

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-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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