Derivative Instruments (Details 2) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative [Line Items]
Expected effect during next twelve months	$ 4.5
Interest expense | Designated as hedging instrument | Interest rate swap, Expired, 2006 secured railcar equipment notes
Derivative [Line Items]
Expired hedges	(0.4)	$ (0.3)	$ (0.3)
Expected effect during next twelve months	(0.2)
Interest expense | Designated as hedging instrument | Interest rate swap, Expired, Promissory notes
Derivative [Line Items]
Expired hedges	0.0	1.2	2.9
Expected effect during next twelve months	0.0
Interest expense | Designated as hedging instrument | Interest rate swap, Expired, TRIP Holdings warehouse loan
Derivative [Line Items]
Expired hedges	4.8	4.9	5.1
Expected effect during next twelve months	4.5
Interest expense | Designated as hedging instrument | Interest Rate Swap, Open, TRIP Master Funding secured railcar equipment notes
Derivative [Line Items]
Open hedges	0.9	1.3	1.5
Expected effect during next twelve months	0.6
Interest expense | Designated as hedging instrument | Interest Rate Swap, Open, Promissory notes
Derivative [Line Items]
Open hedges	0.0	$ 5.3	$ 15.4
Expected effect during next twelve months	$ 0.0