Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Goodwill by Segment
Goodwill	$ 754,100,000	$ 753,800,000
Goodwill, Impairment Loss	0	0
Rail Group
Goodwill by Segment
Goodwill	134,600,000	134,600,000
Goodwill, Impaired, Accumulated Impairment Loss	325,000,000	325,000,000
Construction Products Group
Goodwill by Segment
Goodwill	111,000,000	111,000,000
Energy Equipment Group
Goodwill by Segment
Goodwill	506,700,000	506,400,000
Railcar Leasing and Management Services Group
Goodwill by Segment
Goodwill	$ 1,800,000	$ 1,800,000