Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Financial information for segments
Total revenues	$ 1,676.8	$ 1,485.3	$ 3,303.5	$ 2,945.8
Operating Profit (Loss)	382.9	302.0	716.0	693.3
Intersegment
Financial information for segments
Total revenues	319.4	214.6	676.1	538.4
Total
Financial information for segments
Total revenues	1,996.2	1,699.9	3,979.6	3,484.2
Operating Profit (Loss)	463.6	357.4	870.6	821.1
Corporate
Financial information for segments
Total revenues	0.0	0.0	0.0	0.0
Operating Profit (Loss)	(32.3)	(29.7)	(59.0)	(52.8)
Eliminations – Lease subsidiary
Financial information for segments
Total revenues	(215.5)	(128.6)	(474.5)	(377.7)
Operating Profit (Loss)	(49.9)	(26.9)	(98.2)	(76.2)
Eliminations – Other
Financial information for segments
Total revenues	(103.9)	(86.0)	(201.6)	(160.7)
Operating Profit (Loss)	1.5	1.2	2.6	1.2
Rail Group
Financial information for segments
Total revenues	884.2	760.7	1,759.6	1,361.8
Rail Group | Intersegment
Financial information for segments
Total revenues	226.1	134.9	495.2	391.2
Rail Group | Total
Financial information for segments
Total revenues	1,110.3	895.6	2,254.8	1,753.0
Operating Profit (Loss)	227.7	176.0	440.4	343.5
Construction Products Group
Financial information for segments
Total revenues	148.9	149.9	260.3	262.1
Construction Products Group | Intersegment
Financial information for segments
Total revenues	2.4	1.8	3.8	2.7
Construction Products Group | Total
Financial information for segments
Total revenues	151.3	151.7	264.1	264.8
Operating Profit (Loss)	21.3	22.4	29.6	44.1
Inland Barge Group
Financial information for segments
Total revenues	187.8	165.4	340.9	302.3
Inland Barge Group | Intersegment
Financial information for segments
Total revenues	0.0	0.0	0.0	0.0
Inland Barge Group | Total
Financial information for segments
Total revenues	187.8	165.4	340.9	302.3
Operating Profit (Loss)	40.7	30.9	68.2	57.6
Energy Equipment Group
Financial information for segments
Total revenues	223.3	183.2	464.8	350.2
Energy Equipment Group | Intersegment
Financial information for segments
Total revenues	58.6	44.4	117.2	88.0
Energy Equipment Group | Total
Financial information for segments
Total revenues	281.9	227.6	582.0	438.2
Operating Profit (Loss)	36.3	28.3	73.5	51.2
Railcar Leasing and Management Services Group
Financial information for segments
Total revenues	231.4	225.4	475.6	667.6
Railcar Leasing and Management Services Group | Intersegment
Financial information for segments
Total revenues	6.7	6.1	7.3	7.0
Railcar Leasing and Management Services Group | Total
Financial information for segments
Total revenues	238.1	231.5	482.9	674.6
Operating Profit (Loss)	137.7	102.4	260.5	332.7
All Other
Financial information for segments
Total revenues	1.2	0.7	2.3	1.8
All Other | Intersegment
Financial information for segments
Total revenues	25.6	27.4	52.6	49.5
All Other | Total
Financial information for segments
Total revenues	26.8	28.1	54.9	51.3
Operating Profit (Loss)	$ (0.1)	$ (2.6)	$ (1.6)	$ (8.0)