Summary of Significant Accounting Policies - Leveraged Leases (Details) (Domestic And International Leveraged Lease [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Domestic And International Leveraged Lease [Member]
Net Investments from Leveraged Lease
Net rentals receivable	$ 1,214	$ 1,216
Unearned income	(544)	(567)
Investment in leveraged leases	670	649
Deferred taxes from leveraged leases	(278)	(277)
Net investment in leveraged leases	392	372
Components of Income from Leveraged Lease
Pretax leveraged lease income	21	25	18
Income tax expense	(8)	(9)	(8)
Net leveraged lease income	$ 13	$ 16	$ 10

Leveraged leases net investment in leveraged leases disclosure unearned income.

No definition available.

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The net investment in arrangements meeting the criteria to be classified as leveraged excluding deferred taxes.

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Pretax lease income allocated in proportionate amounts from unearned income.

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The tax effect from the current year income from arrangements meeting the criteria for classification as a leveraged lease.

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The total recognized during the period for income on leases meeting the criteria for classification as leveraged leases.

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Taxes arising from arrangements meeting the criteria for classification as leveraged leases due to timing differences between accounting and tax income recognition.

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

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

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