Railcar Leasing and Management Services Group (Details 3) (Leasing Group [Member], USD $) In Millions, unless otherwise specified	Jun. 30, 2012
Future operating lease obligations related to these 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
Future operating lease obligations of Trusts' railcar [Member]
Future operating lease obligations related to these leases
Remaining six months of 2012	22.7
2013	45.6
2014	44.8
2015	43.1
2016	40.1
Thereafter	341.3
Total	537.6
Future Contractual Minimum Rental Revenues Of Trusts Railcar [Member]
Future operating lease obligations related to these leases
Remaining six months of 2012	30.3
2013	47.2
2014	32.0
2015	23.9
2016	16.2
Thereafter	27.1
Total	$ 176.7

The total of future contractually lease obligations on leases defined as operating.

No definition available.

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, lease obligations within one year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, lease obligations within the fifth year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, lease obligations within the fourth year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, lease obligations after the fifth year from the balance sheet date on leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, lease obligations within the third year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

For leases having an initial or remaining non-cancelable letter-terms in excess of one year, lease obligations within the second year of the balance sheet date relating to leases defined as operating.

+ References

No definition available.

+ Details

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- Definition

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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- Definition

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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- Definition

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

+ References

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- Definition

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

+ References

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- Definition

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

+ References

+ Details

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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

+ Details

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