Investments in Affiliated Companies (Investments and Distributions) (Details 3) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	$ 8.6	$ 38.5	$ 33.9
Equity Method Investment, Net Sales Proceeds	2.3	1.0	24.7
Payments to Acquire Equity Method Investments	36.6	25.0	15.5
Proceeds from Equity Method Investment, Distribution	30.9	36.7	37.3
Rail North America [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	4.6	31.2	2.5
Payments to Acquire Equity Method Investments	0.0	0.0	0.0
Proceeds from Equity Method Investment, Distribution	0.7	1.5	5.1
Rail International [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	0.3	0.6	0.4
Portfolio Management [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	3.7	6.7	31.0
Payments to Acquire Equity Method Investments	36.6	25.0	15.5
Proceeds from Equity Method Investment, Distribution	30.2	$ 35.2	$ 32.2
Adler Funding Llc [Member]
Schedule of Equity Method Investments [Line Items]
Asset Impairment Charges	$ 3.0