Restructuring Activities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	$ 1.0		$ 3.4
Severance Costs	4.1
Restructuring and Related Cost, Incurred Cost	4.1
Payments for Restructuring	(6.5)
Impairment of Long-Lived Assets to be Disposed of	5.2	$ 0.0
Gain (Loss) on Disposition of Assets	(3.8)
Asset Impairment Charges	1.4
Restructuring Charges	5.5	$ 0.0
Employee Severance [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring Reserve	1.0
Operating Segments | Railcar Leasing and Management Services Group [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	0.0
Impairment of Long-Lived Assets to be Disposed of	0.0
Gain (Loss) on Disposition of Assets	0.0
Restructuring Charges	0.0
Operating Segments | Rail Group [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	2.6
Impairment of Long-Lived Assets to be Disposed of	0.0
Gain (Loss) on Disposition of Assets	0.0
Restructuring Charges	2.6
Operating Segments | Other Segments [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	0.1
Impairment of Long-Lived Assets to be Disposed of	0.0
Gain (Loss) on Disposition of Assets	(3.8)
Restructuring Charges	(3.7)
Operating Segments | Corporate, Non-Segment [Member]
Restructuring Cost and Reserve [Line Items]
Severance Costs	1.4
Impairment of Long-Lived Assets to be Disposed of	5.2
Gain (Loss) on Disposition of Assets	0.0
Restructuring Charges	$ 6.6