Railcar Leasing and Management Services Group (Details Textual) (USD $) In Millions, unless otherwise specified	1 Months Ended	12 Months Ended
	Jul. 31, 2011	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Railcar Leasing and Management Services Group (Textual) [Abstract]
Interest expense		$ 185.3	$ 182.1	$ 123.2
Total assets		6,121.0	5,760.0	4,656.4
Railcar Leasing and Management Services Group Additional (Textual) [Abstract]
Operating lease obligations guaranteed		30.3
Value of Seven year Term-Loan agreement				61.0
Capital lease obligations				56.6
Net book value of securing capital lease obligations		51.0
Maturities of lease agreements Years One		2023
Maturities of lease agreements, Year Two		2026
Maturities of lease agreements, Year Three		2027
Year One, of Rail Cars Purchase at predetermined fixed price		2016
Year Two, of Rail Cars Purchase at predetermined fixed price		2019
TRIP Holdings [Member]
Railcar Leasing and Management Services Group (Textual) [Abstract]
Revenue from sale of railcars		0	0	39.4
Operating profit from sale of Rail Cars		0	0	2.0
New debt issued to repay outstanding borrowings of TRIP Warehouse Loan	1,032.0
Leasing Group [Member]
Railcar Leasing and Management Services Group (Textual) [Abstract]
Interest expense		160.8	138.6	80.1
Rent expense		48.6	48.6	46.7
Total assets		4,462.1	4,452.6	3,167.3
Leasing Group [Member] | Wholly Owned Subsidiaries [Member]
Railcar Leasing and Management Services Group (Textual) [Abstract]
Interest expense		101.3	91.7	80.1
Equipment pledged as collateral for Leasing Group debt		1,135.0
Equipment net pledged as collateral for securing capital lease obligations		2,489.1
Period of railcars leased from the Trusts under operating leases		22 years
Total assets		219.1
Cash		88.6
Railcars		97.6
Leasing Group [Member] | TRIP Holdings [Member]
Railcar Leasing and Management Services Group (Textual) [Abstract]
Interest expense		59.5	46.9
New debt issued to repay outstanding borrowings of TRIP Warehouse Loan	$ 1,032.0