Railcar Leasing and Management Services Group (Details 2) (Leasing Group [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2011
Future contractual minimum rental revenues on leases
2012	$ 349.5
2013	268.3
2014	195.4
2015	150.0
2016	110.5
Thereafter	237.5
Total	1,311.2
TRIP Holdings [Member]
Future contractual minimum rental revenues on leases
2012	93.6
2013	62.6
2014	41.9
2015	33.7
2016	28.9
Thereafter	55.7
Total	316.4
Wholly Owned Subsidiaries [Member]
Future contractual minimum rental revenues on leases
2012	255.9
2013	205.7
2014	153.5
2015	116.3
2016	81.6
Thereafter	181.8
Total	$ 994.8

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph b(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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Future rental payments receivable within one year of the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

+ References

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Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

+ References

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Future rental payments receivable within the third year from the balance sheet date under an operating lease.

+ References

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Future rental payments receivable within the second year from the balance sheet date under an operating lease.

+ References

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- Definition

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

+ References

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