Fair Value Disclosure (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011 Instrument	Dec. 31, 2010 Vehicle Instrument
Derivative (Textual) [Abstract]
No. of instruments, outstanding	3	3
Fair Value Disclosure (Textual) [Abstract]
No. of Aluminum hopper railcars having economic life decreased		358
Aggregate fair value of all derivative instruments with Net liability position	$ 2.4
Aggregate notional amount of outstanding Fair value hedge derivative instruments	350.0	350.0
Aggregate notional amount of outstanding Cash flow hedge derivative instruments	73.4	127.0
Expected Pre tax reclassification of net losses from accumulated other comprehensive income to earnings in Next Twelve Months	7.0
Expected After tax reclassification of net losses from accumulated other comprehensive income to earnings in Next Twelve Months	4.4
Aircraft held for lease and helicopter held for sale impairment	4.1
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Impairment Losses [Member]
Additional Fair Value Disclosure (Textual) [Abstract]
Fair Value of Assets	6.7	8.1
Regulatory Mandate [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Impairment Losses [Member]
Additional Fair Value Disclosure (Textual) [Abstract]
Fair Value of Assets		4.8
Scrapped Wheelsets [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Impairment Losses [Member]
Additional Fair Value Disclosure (Textual) [Abstract]
Fair Value of Assets	2.6	1.5
Aircraft Held For Lease And Helicopter Held For Sale [Member] \| Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member] \| Impairment Losses [Member]
Additional Fair Value Disclosure (Textual) [Abstract]
Fair Value of Assets		$ 1.8
Fair Value Hedging [Member]
Derivative (Textual) [Abstract]
Maturity date range of hedge derivatives	2012-2015
Cash Flow Hedging [Member]
Derivative (Textual) [Abstract]
No. of instruments, outstanding	11	12
Maturity date range of hedge derivatives	2012-2014

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Aircraft held for lease and helicopter held for sale impairment.

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Cash flow hedge pre-tax gain (loss) to be reclassified within twelve months.

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Fair value of assets.

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Maturity date Range of derivative instruments.

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Number of aluminum hopper railcars having economic life decreased.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

-Paragraph 45

-Subparagraph b(2)

-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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The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

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The number of derivative instruments of a particular group held by the entity.

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Aggregate notional amount of all derivatives designated as cash flow hedging instruments. The notional amount relates to a number of currency units, shares, bushels, pounds, or other units specified in a derivative instrument.

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- Definition

Aggregate notional amount of all interest rate derivatives designated as hedging instruments in fair value hedges. Notional amount refers to the monetary amount specified in the interest rate derivative contract.

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