Leases (Details 1) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Minimum future lease payments to be received from sales-type and direct financing leases
2012	$ 2,586
2013	2,581
2014	3,751
2015	1,288
2016	378
Thereafter	$ 298

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Future rental payments receivable within one year of the balance sheet date on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6952072&loc=d3e45377-112738

+ Details

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- Definition

Future lease rental payments receivable after the fifth year from the balance sheet date on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6952072&loc=d3e45377-112738

+ Details

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- Definition

Future lease rental payments receivable within the fifth year from the balance sheet date on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

+ Details

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- Definition

Future lease rental payments receivable within the fourth year from the balance sheet date on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

+ Details

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- Definition

Future lease rental payments receivable within the third year from the balance sheet date on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

+ Details

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- Definition

Future rental payments receivable within the second year from the balance sheet date on nonoperating leases (direct financing, sales-type and leveraged leases).

+ References

+ Details

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