Derivative Instruments (Details 1) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Interest rate swap, Expired, 2006 secured railcar equipment notes | Interest expense | Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Effect on interest expense		$ 0.0	$ (0.1)	$ (0.2)	$ (0.3)
Expected effect during next twelve months	[1]	(0.3)		(0.3)
Interest rate swap, Expired, Promissory notes | Interest expense | Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Effect on interest expense		0.0	0.7	1.2	2.2
Expected effect during next twelve months	[1]	0.0		0.0
Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative Instruments, Gain (Loss) [Line Items]
Expected effect during next twelve months		4.8		4.8
Interest rate swap, Expired, TRIP Holdings warehouse loan | Interest expense | Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Effect on interest expense		1.2	1.3	3.7	3.9
Expected effect during next twelve months	[1]	4.8		4.8
Interest rate swap, Open, TRIP Master Funding secured railcar equipment notes | Interest expense | Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss on derivative, net		0.2	0.4	0.9	1.2
Expected effect during next twelve months	[1]	1.0		1.0
Interest rate swap, Open, Promissory notes | Interest expense | Designated as hedging instrument
Derivative Instruments, Gain (Loss) [Line Items]
Loss on derivative, net		0.0	$ 3.8	5.3	$ 11.5
Expected effect during next twelve months	[1]	$ 0.0		$ 0.0

[1] Based on the fair value of open hedges as of September 30, 2015