Derivative Instruments (Details 1) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative Instruments, Gain (Loss) [Line Items]
Expected effect during next twelve months	$ 3.5		$ 3.5
Interest expense | Designated as hedging instrument | Interest rate swap, Expired, 2006 secured railcar equipment notes
Derivative Instruments, Gain (Loss) [Line Items]
Effect on interest expense	0.0	$ (0.1)	(0.1)	$ (0.2)
Expected effect during next twelve months	(0.2)		(0.2)
Interest expense | Designated as hedging instrument | Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative Instruments, Gain (Loss) [Line Items]
Effect on interest expense	1.1	1.2	2.3	2.4
Expected effect during next twelve months	3.5		3.5
Interest expense | Designated as hedging instrument | Interest rate swap, Open, TRIP Master Funding secured railcar equipment notes
Derivative Instruments, Gain (Loss) [Line Items]
Loss on derivative, net	0.1	$ 0.2	0.3	$ 0.5
Expected effect during next twelve months	$ 0.4		$ 0.4