Railcar Leasing and Management Services Group (Details 4) (Leasing Group [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2012
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
Remaining nine months of 2012	$ 271.8
2013	289.8
2014	217.3
2015	167.7
2016	125.8
Thereafter	251.0
Total	1,323.4
Future Operating Lease Obligations [Member]
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
Remaining nine months of 2012	6.5
2013	8.4
2014	8.3
2015	8.3
2016	8.1
Thereafter	35.6
Total	75.2
Future Contractual Minimum Rental Revenues [Member]
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
Remaining nine months of 2012	7.4
2013	9.1
2014	8.6
2015	5.1
2016	4.3
Thereafter	7.6
Total	$ 42.1

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The total of future contractually required payments on leases defined as operating.

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For leases having an initial or remaining non-cancelable letter-terms in excess of one year, required rental payments due within the fifth year of the balance sheet date relating to leases defined as operating.

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Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

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