Railcar Leasing and Management Services Group (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Consolidating Financial Information
Cash, cash equivalents, and short-term marketable securities	$ 798.1	$ 870.9
Property, plant, and equipment, net	5,966.8	5,348.0
Restricted cash	178.2	195.8
Debt:
Recourse	881.5	885.7
Less: unamortized discount	(27.1)	(44.2)
Less: unamortized debt issuance costs	(3.8)	(4.8)
Recourse, net of unamortized discount and unamortized debt issuance costs	850.6	836.7
Non-recourse	2,232.4	2,390.7
Less: unamortized debt issuance costs	(26.4)	(32.0)
Non-recourse debt, net of unamortized debt issuance costs	2,206.0	2,358.7
Total debt	3,056.6	3,195.4
Net_deferred_tax_liabilities_(assets)	1,057.0	734.8
Wholly-owned subsidiaries
Debt:
Non-recourse debt, net of unamortized debt issuance costs	840.0	928.7
Partially-owned subsidiaries
Consolidating Financial Information
Restricted cash	78.4	89.9
Debt:
Non-recourse debt, net of unamortized debt issuance costs	1,366.0	1,430.0
Manufacturing/Corporate
Consolidating Financial Information
Property, plant, and equipment, net	961.7	956.1
Leasing Group
Debt:
Non-recourse debt, net of unamortized debt issuance costs	2,206.0	2,358.7
Leasing Group \| Wholly-owned subsidiaries
Debt:
Non-recourse	851.4	943.8
Less: unamortized debt issuance costs	(11.4)	(15.1)
Non-recourse debt, net of unamortized debt issuance costs	840.0	928.7
Leasing Group \| Partially-owned subsidiaries
Debt:
Non-recourse	1,381.0	1,446.9
Less: unamortized debt issuance costs	(15.0)	(16.9)
Non-recourse debt, net of unamortized debt issuance costs	1,366.0	1,430.0
Operating Segments
Consolidating Financial Information
Property, plant, and equipment, net	6,764.9	6,021.0
Operating Segments \| Manufacturing/Corporate
Consolidating Financial Information
Property, plant, and equipment, net	961.7	956.1
Operating Segments \| Leasing Group \| Wholly-owned subsidiaries
Consolidating Financial Information
Cash, cash equivalents, and short-term marketable securities	7.2	3.8
Property, plant, and equipment, net	3,923.6	3,126.3
Restricted cash	99.7	105.9
Debt:
Recourse	32.1	35.8
Less: unamortized discount	0.0	0.0
Less: unamortized debt issuance costs	(0.1)	(0.1)
Recourse, net of unamortized discount and unamortized debt issuance costs	32.0	35.7
Non-recourse	851.4	943.8
Less: unamortized debt issuance costs	(11.4)	(15.1)
Non-recourse debt, net of unamortized debt issuance costs	840.0	928.7
Total debt	872.0	964.4
Net_deferred_tax_liabilities_(assets)	956.6	746.0
Operating Segments \| Leasing Group \| Partially-owned subsidiaries
Consolidating Financial Information
Cash, cash equivalents, and short-term marketable securities	0.0	0.0
Property, plant, and equipment, net	1,879.6	1,938.6
Restricted cash	78.4	89.9
Debt:
Recourse	0.0	0.0
Less: unamortized discount	0.0	0.0
Less: unamortized debt issuance costs	0.0	0.0
Recourse, net of unamortized discount and unamortized debt issuance costs	0.0	0.0
Non-recourse	1,381.0	1,446.9
Less: unamortized debt issuance costs	(15.0)	(16.9)
Non-recourse debt, net of unamortized debt issuance costs	1,366.0	1,430.0
Total debt	1,366.0	1,430.0
Net_deferred_tax_liabilities_(assets)	2.0	1.4
Operating Segments \| Manufacturing/Corporate \| Manufacturing/Corporate
Consolidating Financial Information
Cash, cash equivalents, and short-term marketable securities	790.9	867.1
Restricted cash	0.1	0.0
Debt:
Recourse	849.4	849.9
Less: unamortized discount	(27.1)	(44.2)
Less: unamortized debt issuance costs	(3.7)	(4.7)
Recourse, net of unamortized discount and unamortized debt issuance costs	818.6	801.0
Non-recourse	0.0	0.0
Less: unamortized debt issuance costs	0.0	0.0
Non-recourse debt, net of unamortized debt issuance costs	0.0	0.0
Total debt	818.6	801.0
Net_deferred_tax_liabilities_(assets)	98.4	(12.6)
Intersegment
Consolidating Financial Information
Property, plant, and equipment, net	$ (798.1)	$ (673.0)

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