Fair Value Accounting (Details 2) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Capital lease obligations	$ 885.7	$ 889.3
Less: unamortized discount	(44.2)	(60.0)
Less: unamortized debt issuance costs	(4.8)	(5.7)
Recourse, net of unamortized discount and unamortized debt issuance costs	836.7	823.6
Non-recourse debt	2,390.7	2,723.7
Less: unamortized debt issuance costs	(32.0)	(32.8)
Non-recourse debt, net of unamortized debt issuance costs	2,358.7	2,690.9
Total debt	3,195.4	3,514.5
Carrying Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	841.5	829.3
Less: unamortized debt issuance costs	(4.8)	(5.7)
Recourse, net of unamortized discount and unamortized debt issuance costs	836.7	823.6
Non-recourse debt	2,390.7	2,723.7
Less: unamortized debt issuance costs	(32.0)	(32.8)
Non-recourse debt, net of unamortized debt issuance costs	2,358.7	2,690.9
Total debt	3,195.4	3,514.5
Carrying Value \| 2006 secured railcar equipment notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	204.1	223.0
Carrying Value \| 2009 secured railcar equipment notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	179.2	188.8
Carrying Value \| 2010 secured railcar equipment notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	296.2	311.5
Carrying Value \| TRL 2012 secured railcar equipment notes (RIV 2013)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	449.1	472.2
Carrying Value \| TRIP Master Funding secured railcar equipment notes (TRIP Holdings)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	997.8	1,043.7
Carrying Value \| Senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	399.6	399.6
Carrying Value \| Convertible subordinated notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	405.6	389.9
Capital lease obligations	449.4	449.5
Less: unamortized discount	(43.8)	(59.6)
Carrying Value \| Capital lease obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	35.8	39.1
Carrying Value \| Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	0.5	0.7
Carrying Value \| Promissory notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	0.0	363.9
Carrying Value \| Line of credit \| TILC warehouse facility \| Revolving credit facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	264.3	120.6
Estimated Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	941.4	1,020.7
Non-recourse debt	2,480.3	2,892.3
Total debt	3,421.7	3,913.0
Estimated Fair Value \| 2006 secured railcar equipment notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	218.2	245.6
Estimated Fair Value \| 2009 secured railcar equipment notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	207.2	227.7
Estimated Fair Value \| 2010 secured railcar equipment notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	314.2	344.0
Estimated Fair Value \| TRL 2012 secured railcar equipment notes (RIV 2013)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	436.9	470.3
Estimated Fair Value \| TRIP Master Funding secured railcar equipment notes (TRIP Holdings)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	1,039.5	1,121.4
Estimated Fair Value \| Senior notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	370.3	387.0
Estimated Fair Value \| Convertible subordinated notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Capital lease obligations	534.8	593.9
Estimated Fair Value \| Capital lease obligations
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	35.8	39.1
Estimated Fair Value \| Other
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt, including unamortized debt issuance costs, net of unamortized discount	0.5	0.7
Estimated Fair Value \| Promissory notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	0.0	362.7
Estimated Fair Value \| Line of credit \| TILC warehouse facility \| Revolving credit facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Non-recourse debt	$ 264.3	$ 120.6

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