Debt (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Components of debt
Less: unamortized discount	$ (96.8)	$ (99.8)
Total Recourse Debt	461.2	457.7
TRIP Holdings senior secured notes:
Less: owned by Trinity	(108.8)	(108.8)
Total non-recourse debt	2,466.3	2,517.2
Total debt	2,927.5	2,974.9
Manufacturing/Corporate Recourse [Member]
Components of debt
Revolving credit facility
Convertible subordinated notes	450.0	450.0
Less: unamortized discount	(96.8)	(99.8)
Convertible subordinated notes, total	353.2	350.2
Other	6.1	4.2
Total Manufacturing/Corporate - Recourse Debt	359.3	354.4
Leasing - Recourse [Member]
Components of debt
Capital lease obligations	47.9	48.6
Term loan	54.0	54.7
Leasing Recourse	101.9	103.3
Leasing - Non-Recourse [Member]
Components of debt
2006 secured railcar equipment notes	266.0	269.3
Promissory notes	459.3	465.5
2009 secured railcar equipment notes	216.2	218.4
2010 secured railcar equipment notes	351.3	354.3
TILC warehouse facility	282.7	308.5
TRIP Holdings senior secured notes:
Total outstanding	170.0	170.0
Less: owned by Trinity	(108.8)	(108.8)
TRIP Holdings senior secured notes	61.2	61.2
TRIP Master Funding secured railcar equipment notes	$ 829.6	$ 840.0

Capital Lease Obligations And Term Loan.

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Convertible subordinated debt gross.

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Debt recourse consisting of secured and unsecured debt, net of unamortized discount.

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Debt recourse net of unamortized discount including secured and unsecured debt excluding loans payable and capital lease obligations.

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Promissory notes.

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Secured debt owned exclusively by parent company.

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Secured Railcar equipment notes one.

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Secured Railcar equipment notes three.

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Secured Railcar equipment notes two.

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Senior secured debt owned but not exclusively owned by parent company.

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Subsidiary secured railcar equipment notes.

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Subsidiary warehouse facility.

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Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date.

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Including the current and noncurrent portions, the carrying value of convertible subordinated debt, as of the balance sheet date, initially scheduled to be repaid after one year or beyond the normal operating cycle if longer. This form of debt can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder, and places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

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Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Including the current and noncurrent portions, aggregate carrying value as of the balance sheet date of loans payable (with maturities initially due after one year or beyond the operating cycle if longer).

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Including both current and noncurrent portions, carrying amount as of the balance sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Carrying value as of the balance sheet date , including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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