Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Financial information for segments
Total revenues	$ 1,626.7	$ 1,460.5
Operating Profit (Loss)	333.1	391.3
Rail Group
Financial information for segments
Total revenues	875.4	601.1
Operating Profit (Loss)	212.7	167.5
Construction Products Group
Financial information for segments
Total revenues	111.4	112.2
Operating Profit (Loss)	8.3	21.7
Inland Barge Group
Financial information for segments
Total revenues	153.1	136.9
Operating Profit (Loss)	27.5	26.7
Energy Equipment Group
Financial information for segments
Total revenues	241.5	167.0
Operating Profit (Loss)	37.2	22.9
Railcar Leasing and Management Services Group
Financial information for segments
Total revenues	244.2	442.2
Operating Profit (Loss)	122.8	230.3
All Other
Financial information for segments
Total revenues	1.1	1.1
Operating Profit (Loss)	(1.5)	(5.4)
Segment Totals before Eliminations and Corporate Expenses
Financial information for segments
Total revenues	1,626.7	1,460.5
Operating Profit (Loss)	407.0	463.7
Corporate
Financial information for segments
Total revenues	0	0
Operating Profit (Loss)	(26.7)	(23.1)
Eliminations – Lease subsidiary
Financial information for segments
Total revenues	0	0
Operating Profit (Loss)	(48.3)	(49.3)
Eliminations – Other
Financial information for segments
Total revenues	0	0
Operating Profit (Loss)	1.1	0
Total
Financial information for segments
Total revenues	1,626.7	1,460.5
Total | Rail Group
Financial information for segments
Total revenues	1,144.5	857.4
Total | Construction Products Group
Financial information for segments
Total revenues	112.8	113.1
Total | Inland Barge Group
Financial information for segments
Total revenues	153.1	136.9
Total | Energy Equipment Group
Financial information for segments
Total revenues	300.1	210.6
Total | Railcar Leasing and Management Services Group
Financial information for segments
Total revenues	244.8	443.1
Operating Profit (Loss)	122.8	230.3
Total | All Other
Financial information for segments
Total revenues	28.1	23.2
Total | Segment Totals before Eliminations and Corporate Expenses
Financial information for segments
Total revenues	1,983.4	1,784.3
Total | Corporate
Financial information for segments
Total revenues	0	0
Total | Eliminations – Lease subsidiary
Financial information for segments
Total revenues	(259.0)	(249.1)
Total | Eliminations – Other
Financial information for segments
Total revenues	(97.7)	(74.7)
Intersegment
Financial information for segments
Total revenues	0	0
Intersegment | Rail Group
Financial information for segments
Total revenues	269.1	256.3
Intersegment | Construction Products Group
Financial information for segments
Total revenues	1.4	0.9
Intersegment | Inland Barge Group
Financial information for segments
Total revenues	0	0
Intersegment | Energy Equipment Group
Financial information for segments
Total revenues	58.6	43.6
Intersegment | Railcar Leasing and Management Services Group
Financial information for segments
Total revenues	0.6	0.9
Intersegment | All Other
Financial information for segments
Total revenues	27.0	22.1
Intersegment | Segment Totals before Eliminations and Corporate Expenses
Financial information for segments
Total revenues	356.7	323.8
Intersegment | Corporate
Financial information for segments
Total revenues	0	0
Intersegment | Eliminations – Lease subsidiary
Financial information for segments
Total revenues	(259.0)	(249.1)
Intersegment | Eliminations – Other
Financial information for segments
Total revenues	$ (97.7)	$ (74.7)