Railcar Leasing and Management Services Group (Details 3) (Leasing Group [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2012
Future operating lease obligations and future contractual minimum rental revenues related to these 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
Future operating lease obligations of Trusts' railcar [Member]
Future operating lease obligations and future contractual minimum rental revenues related to these leases
Remaining nine months of 2012	33.6
2013	45.6
2014	44.8
2015	43.1
2016	40.1
Thereafter	341.3
Total	548.5
Future Contractual Minimum Rental Revenues Of Trusts Railcar [Member]
Future operating lease obligations and future contractual minimum rental revenues related to these leases
Remaining nine months of 2012	44.8
2013	44.2
2014	29.7
2015	22.2
2016	14.5
Thereafter	26.1
Total	$ 181.5

The total of future contractually required payments on leases defined as operating.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 122

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 Statement of Financial Accounting Standard (FAS)

-Number 13

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-SubTopic 10

-Section 55

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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.

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-Name Accounting Standards Codification

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