Debt (Details 1) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Unamortized Debt Issuance Expense	$ 4.3		$ 4.3		$ 4.8
3 7/8% Convertible Subordinated Notes Due 2036 [Member] | Convertible subordinated notes
Debt Instrument [Line Items]
Coupon rate interest	4.3	$ 4.3	8.7	$ 8.7
Amortized debt discount	4.2	3.9	8.4	7.7
Total interest expense recognized on the Convertible Subordinated Notes	8.5	$ 8.2	17.1	$ 16.4
Railcar Leasing and Management Services Group | Capital lease obligations, net of unamortized debt issuances costs of $0.1 and $0.1
Debt Instrument [Line Items]
Unamortized Debt Issuance Expense	$ 0.1		$ 0.1		$ 0.1