Railcar Leasing and Management Services Group (Details 2) (Leasing Group [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Future contractual minimum rental revenues on leases
Remaining six months of 2012	$ 188.5
2013	315.4
2014	241.8
2015	190.5
2016	147.8
Thereafter	283.8
Total	1,367.8
Wholly Owned Subsidiaries [Member]
Future contractual minimum rental revenues on leases
Remaining six months of 2012	140.8
2013	239.8
2014	187.4
2015	146.1
2016	110.5
Thereafter	219.0
Total	1,043.6
TRIP Holdings [Member]
Future contractual minimum rental revenues on leases
Remaining six months of 2012	47.7
2013	75.6
2014	54.4
2015	44.4
2016	37.3
Thereafter	64.8
Total	$ 324.2

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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