Railcar Leasing and Management Services Group (Details 4) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
2012	$ 4.3
2013	2.4
2014	1.7
2015	1.3
2016	1.0
Thereafter	1.9
Leasing Group [Member]
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
2012	349.5
2013	268.3
2014	195.4
2015	150.0
2016	110.5
Thereafter	237.5
Total	1,311.2
Leasing Group [Member] \| Future Operating Lease Obligations [Member]
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
2012	8.3
2013	8.0
2014	7.9
2015	7.9
2016	7.7
Thereafter	33.4
Total	73.2
Leasing Group [Member] \| Future Contractual Minimum Rental Revenues [Member]
Future contractual minimum rental revenues related to operating leases other than leases with the Trusts
2012	9.4
2013	8.5
2014	7.9
2015	5.0
2016	4.3
Thereafter	7.5
Total	$ 42.6

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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 one year of the balance sheet date relating to 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 rental payments in aggregate as of the balance sheet date under operating leases.

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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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