Long-term Commitments (Operating Lease Agreements) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Long-Term Commitments [Abstract]
2012, Gross Rental Commitments	$ 412
2013, Gross Rental Commitments	368
2014, Gross Rental Commitments	316
2015, Gross Rental Commitments	275
2016, Gross Rental Commitments	236
Subsequent years, Gross Rental Commitments	1,133
2012, Rentals from Subleases	49
2013, Rentals from Subleases	45
2014, Rentals from Subleases	43
2015, Rentals from Subleases	39
2016, Rentals from Subleases	39
Subsequent years, Rentals from Subleases	142
2012, Net Rental Commitments	363
2013, Net Rental Commitments	323
2014, Net Rental Commitments	273
2015, Net Rental Commitments	236
2016, Net Rental Commitments	197
Subsequesnt years, Net Rental Commitments	$ 991

Gross Rental Commitments Five Year

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Gross Rental Commitments Four Year

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Gross Rental Commitments One Year

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Gross Rental Commitments Thereafter

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Gross Rental Commitments Three Year

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- Definition

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases after the fifth year following the balance sheet date.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 98

-Paragraph 18

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the fifth year following the balance sheet date.

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This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the fourth year following the balance sheet date.

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This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within one year of the balance sheet date.

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This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the third year following the balance sheet date.

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This element represents the total of minimum sublease rentals, if any, to be received under noncancelable subleases within the second year following the balance sheet date.

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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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-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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-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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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.

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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 third 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.

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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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