Investments (Details 49) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Investment in leveraged leases
Rental receivables, net	$ 1,859	$ 1,882
Estimated residual values	1,657	1,682
Subtotal	3,516	3,564
Unearned income	(1,268)	(1,373)
Investment in leveraged leases	$ 2,248	$ 2,191

This element represents the subtotal of rental receivables, net plus estimated residual value of the leased assets.

No definition available.

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Period Type:	instant

- Definition

The estimated portion of pretax income and investment tax credit remaining to be allocated to income over the lease term.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 43

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

-Publisher FASB

-Name Accounting Standards Codification

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-Section 30

-Paragraph 14

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- Definition

The net investment in arrangements meeting the criteria for classification as leveraged leases including deferred taxes.

+ References

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

-Publisher FASB

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

This element represents leveraged lease rentals receivable, net of that portion of the rental applicable to principal and interest on the nonrecourse debt.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 43, 44

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

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- Definition

The estimate of the value of the leased asset at the end of the lease term.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 43

-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

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+ Details

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