Railcar Leasing and Management Services Group (Details 1) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Revenues:
Total revenues	$ 142.1	$ 119.8
Operating Profit:
Total operating profit	122.4	85.5
Interest and rent expense:
Total interest expense	47.9	44.5
Leasing Group [Member]
Revenues:
Total revenues	142.3	119.8
Percent Change	18.80%
Operating Profit:
Total operating profit	66.5	54.7
Operating profit margin:
Total operating profit margin	46.70%	45.70%
Interest and rent expense:
Rent expense	12.7	12.1
Total interest expense	43.1	36.7
Leasing Group [Member] | Leasing and management [Member]
Operating profit margin:
Total operating profit margin	47.00%	44.70%
Leasing Group [Member] | Wholly Owned Subsidiaries [Member]
Revenues:
Total revenues	113.2	90.3
Percent Change	25.40%
Operating Profit:
Total operating profit	50.1	37.5
Interest and rent expense:
Total interest expense	24.6	25.2
Leasing Group [Member] | Wholly Owned Subsidiaries [Member] | Leasing and management [Member]
Revenues:
Total revenues	98.3	90.3
Percent Change	8.90%
Operating Profit:
Total operating profit	43.1	36.5
Leasing Group [Member] | Wholly Owned Subsidiaries [Member] | Sales of cars from the lease fleet [Member]
Revenues:
Total revenues	14.9
Leasing Group [Member] | Wholly Owned Subsidiaries [Member] | Railcar Owned One Year or Less [Member]
Operating Profit:
Total operating profit	2.9
Leasing Group [Member] | Wholly Owned Subsidiaries [Member] | Railcar Owned Greater than One Year [Member]
Operating Profit:
Total operating profit	4.1	1.0
Leasing Group [Member] | TRIP Holdings [Member]
Revenues:
Total revenues	29.1	29.5
Percent Change	(1.40%)
Operating Profit:
Total operating profit	16.4	17.2
Interest and rent expense:
Interest expense external	15.2	11.5
Interest expense intercompany	3.3
Total interest expense	18.5	11.5
Leasing Group [Member] | TRIP Holdings [Member] | Leasing and management [Member]
Revenues:
Total revenues	29.1	29.5
Percent Change	(1.40%)
Operating Profit:
Total operating profit	16.8	17.1
Leasing Group [Member] | TRIP Holdings [Member] | Sales of cars from the lease fleet [Member]
Revenues:
Percent Change
Leasing Group [Member] | TRIP Holdings [Member] | Railcar Owned One Year or Less [Member]
Operating Profit:
Total operating profit
Leasing Group [Member] | TRIP Holdings [Member] | Railcar Owned Greater than One Year [Member]
Operating Profit:
Total operating profit	$ (0.4)	$ 0.1