Railcar Leasing and Management Services Group (Details 2) (Leasing Group [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2012
Future contractual minimum rental revenues on leases
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
TRIP Holdings [Member]
Future contractual minimum rental revenues on leases
Remaining nine months of 2012	71.4
2013	69.3
2014	48.8
2015	39.6
2016	33.1
Thereafter	62.6
Total	324.8
Wholly Owned Subsidiaries [Member]
Future contractual minimum rental revenues on leases
Remaining nine months of 2012	200.4
2013	220.5
2014	168.5
2015	128.1
2016	92.7
Thereafter	188.4
Total	$ 998.6

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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