Commitments (Summary Of Credit-Related Commitments And Purchase And Funding Commitments) (Details) (USD $) In Millions	Jun. 30, 2011	Dec. 31, 2010
Financing and leasing assets - Due to Expire Within One Year	$ 276.8
Financing and leasing assets - Due to Expire After One Year	2,339.1
Financing and leasing assets - Total Outstanding	2,615.9	3,083.2
Standby letters of credit - Due to Expire Within One Year	78.3
Standby letters of credit - Due to Expire After One Year	162.8
Standby letters of credit - Total Outstanding	241.1	284.7
Other letters of credit - Due to Expire Within One Year	101.0
Other letters of credit - Due to Expire After One Year	32.7
Other letters of credit - Total Outstanding	133.7	99.0
Deferred purchase credit protection agreements - Due to Expire Within One Year	1,244.0
Deferred purchase credit protection agreements - Due to Expire After One Year	0
Deferred purchase credit protection agreements - Total Outstanding	1,244.0	1,667.9
Guarantees, acceptances and other recourse obligations - Due to Expire Within One Year	13.5
Guarantees, acceptances and other recourse obligations - Total Outstanding	34.8	25.8
Guarantees, acceptances and other recourse obligations - Due to Expire After One Year	21.3
Liabilities for unrecognized tax benefits - Due to Expire Within One Year	10.0
Liabilities for unrecognized tax benefits - Due to Expire After One Year	442.1
Liabilities for unrecognized tax benefits - Total Outstanding	452.1	451.6
Rail And Other Manufacturer [Member]
Aerospace and other manufacturer purchase commitments - Due to Expire Within One Year	486.4
Aerospace and other manufacturer purchase commitments - Due to Expire After One Year	0
Aerospace and other manufacturer purchase commitments - Total Outstanding	486.4	0
Aerospace Manufacturer [Member]
Aerospace and other manufacturer purchase commitments - Due to Expire Within One Year	926.9
Aerospace and other manufacturer purchase commitments - Due to Expire After One Year	6,978.0
Aerospace and other manufacturer purchase commitments - Total Outstanding	$ 7,904.9	$ 5,701.4

Deferred Purchase Credit Protection Agreements After One Year

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Deferred Purchase Credit Protection Agreements Total Outstanding

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Deferred Purchase Credit Protection Agreements Within One Year

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Financing and Leasing Assets on Commitments Amount Outstanding

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Financing and Leasing Assets on Commitments Current

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Financing and Leasing Assets on Commitments Noncurrent

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Guarantees Acceptances and Other Recourse Obligations Due Current

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Guarantees Acceptances and Other Recourse Obligations Due Noncurrent

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Guarantees Acceptances And Other Recourse Obligations - Total Outstanding

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Liability For Uncertain Tax Positions Total Outstanding

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Other Letters of Credit After One Year

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Other Letters of Credit Total Outstanding

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Other Letters of Credit Within One Year

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Recorded Unconditional Purchase Obligations Due After One Year

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Recorded Unconditional Purchase Obligations Within One Year

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Standby Letters Of Credit

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Standby Letters Of Credit Current

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Standby Letters Of Credit Noncurrent

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The current portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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The noncurrent portion of the amount recognized for uncertain tax positions as of the balance sheet date.

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The carrying amount of the long-term purchase obligation as of the balance sheet date, which equals the sum of all payments due.

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