Other Material Contingencies (Narrative) (Details) (USD $) In Millions	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Lease in lease out total investment	$ 259
Lease in lease out total financed by equity	93
Lease in lease out total financed by long-term debt	166
The company's investment in leverage leases	(48)	(41)
Gross investment in leverage leases	234	235
Deferred tax liabilities	282	276
Tax savings from lease in lease out transactions	229
Guarantee obligations maximum exposure	834	859
Tax Deficiency Paid in December 2005 [Member]
Tax deficiency paid to IRS	0.3
Interest in April 2006 [Member]
Interest paid related to tax deficiency	0.2
Interest up to March 2011 [Member]
Interest paid related to tax deficiency	82.0
Disallowance of Tax 1998-2007 [Member]
Disallowed deduction	416
Disallowance of Tax 2009 [Member]
Disallowed deduction	41
Disallowance of Tax 2008 [Member]
Disallowed deduction	$ 42

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Lease in lease out total financed by equity

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The amount as of the balance sheet date of the estimated future tax effects attributable to differences between the methods used to account for leasing arrangements for tax purposes and under generally accepted accounting principles which will increase future taxable income when such differences reverse.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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

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