Segment Information (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Segment Reporting Information [Line Items]
Total revenues	$ 1,542.2	$ 1,562.8	$ 4,845.7	$ 4,508.6
Operating Profit (Loss)	364.9	281.2	1,080.9	974.5
Intersegment
Segment Reporting Information [Line Items]
Total revenues	418.6	276.7	1,094.7	815.1
Total
Segment Reporting Information [Line Items]
Total revenues	1,960.8	1,839.5	5,940.4	5,323.7
Operating Profit (Loss)	471.3	352.7	1,341.9	1,173.8
Corporate
Segment Reporting Information [Line Items]
Operating Profit (Loss)	(39.7)	(36.7)	(98.7)	(89.5)
Eliminations – Lease subsidiary
Segment Reporting Information [Line Items]
Total revenues	(308.4)	(186.5)	(782.9)	(564.2)
Operating Profit (Loss)	(65.6)	(34.3)	(163.8)	(110.5)
Eliminations – Other
Segment Reporting Information [Line Items]
Total revenues	(110.2)	(90.2)	(311.8)	(250.9)
Operating Profit (Loss)	(1.1)	(0.5)	1.5	0.7
Rail Group
Segment Reporting Information [Line Items]
Total revenues	747.2	802.3	2,506.8	2,164.1
Rail Group | Intersegment
Segment Reporting Information [Line Items]
Total revenues	326.2	194.1	821.4	585.3
Rail Group | Total
Segment Reporting Information [Line Items]
Total revenues	1,073.4	996.4	3,328.2	2,749.4
Operating Profit (Loss)	223.3	186.4	663.7	529.9
Construction Products Group
Segment Reporting Information [Line Items]
Total revenues	151.1	168.4	411.4	430.5
Construction Products Group | Intersegment
Segment Reporting Information [Line Items]
Total revenues	3.7	2.0	7.5	4.7
Construction Products Group | Total
Segment Reporting Information [Line Items]
Total revenues	154.8	170.4	418.9	435.2
Operating Profit (Loss)	19.9	21.6	49.5	65.7
Inland Barge Group
Segment Reporting Information [Line Items]
Total revenues	164.8	168.4	505.7	470.7
Inland Barge Group | Intersegment
Segment Reporting Information [Line Items]
Total revenues	0.0	0.0	0.0	0.0
Inland Barge Group | Total
Segment Reporting Information [Line Items]
Total revenues	164.8	168.4	505.7	470.7
Operating Profit (Loss)	28.1	31.0	96.3	88.6
Energy Equipment Group
Segment Reporting Information [Line Items]
Total revenues	229.6	219.0	694.4	569.2
Energy Equipment Group | Intersegment
Segment Reporting Information [Line Items]
Total revenues	59.9	50.7	177.1	138.7
Energy Equipment Group | Total
Segment Reporting Information [Line Items]
Total revenues	289.5	269.7	871.5	707.9
Operating Profit (Loss)	44.8	30.0	118.3	81.2
Railcar Leasing and Management Services Group
Segment Reporting Information [Line Items]
Total revenues	246.6	203.0	722.2	870.6
Railcar Leasing and Management Services Group | Intersegment
Segment Reporting Information [Line Items]
Total revenues	2.6	2.7	9.9	9.7
Railcar Leasing and Management Services Group | Total
Segment Reporting Information [Line Items]
Total revenues	249.2	205.7	732.1	880.3
Operating Profit (Loss)	158.2	87.0	418.7	419.7
All Other
Segment Reporting Information [Line Items]
Total revenues	2.9	1.7	5.2	3.5
All Other | Intersegment
Segment Reporting Information [Line Items]
Total revenues	26.2	27.2	78.8	76.7
All Other | Total
Segment Reporting Information [Line Items]
Total revenues	29.1	28.9	84.0	80.2
Operating Profit (Loss)	$ (3.0)	$ (3.3)	$ (4.6)	$ (11.3)