Railcar Leasing and Management Services Group (Details 3) (Leasing Group, USD $) In Millions, unless otherwise specified	Mar. 31, 2013
Future contractual minimum rental revenues on leases
Remaining nine months of 2013	$ 303.0
2014	330.1
2015	271.6
2016	213.8
2017	155.3
Thereafter	294.9
Total	1,568.7
Future operating lease obligations of Trusts' railcars
Future contractual minimum rental obligations on leases
Remaining nine months of 2013	34.1
2014	44.7
2015	43.0
2016	40.1
2017	41.9
Thereafter	298.9
Total	502.7
Future contractual minimum rental revenues of Trusts' railcars
Future contractual minimum rental revenues on leases
Remaining nine months of 2013	44.5
2014	46.2
2015	36.0
2016	26.1
2017	17.0
Thereafter	34.7
Total	$ 204.5

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