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- Definition

Date Through Which Equity is Committed

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Date Through Which Equity is Committed, Extended Date

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- Definition

Number of Board Members

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Number of Board Members of Subsidiary, Designated by Parent

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- Definition

Number of Railcars Owned

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Number of subsidiaries.

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Parent Company Guarantees

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- Definition

Remaining equity commitment outstanding.

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Remaining Equity Commitment Outstanding from Third Parties

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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The cash inflow associated with the amount received by a corporation from a shareholder during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

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The cash inflow from parent as a source of financing that is recorded as additional paid in capital.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

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Partially-Owned Leasing Subsidiaries (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	May 31, 2014
Schedule of Investments [Line Items]
Contribution from third-party investors to TRIP Holdings	$ 49.6us-gaap_ProceedsFromContributedCapital	$ 50.0us-gaap_ProceedsFromContributedCapital	$ 0us-gaap_ProceedsFromContributedCapital
Partially-owned subsidiaries
Schedule of Investments [Line Items]
Trinity guarantees of subsidiary-related activities	0
Railcar Leasing and Management Services Group \| Partially-owned subsidiaries
Schedule of Investments [Line Items]
Number of subsidiaries	2
Number of board members	7
Number of TILC designated board members	2
Carrying value of investment in partially-owned subsidiaries	229.1
Ownership percentage in partially-owned subsidiaries	39.00%
Railcar Leasing and Management Services Group \| TRIP Rail Leasing
Schedule of Investments [Line Items]
Number of railcars owned	0
Railcar Leasing and Management Services Group \| TRIP Holdings
Schedule of Investments [Line Items]
Date through which equity funding is committed	May 2016
Remaining equity commitment outstanding from TILC	5.7
Remaining equity commitment outstanding from third parties	12.9
Date through which equity is committed, extended date	May 2019
Contribution from TILC to TRIP Holdings				21.6
Contribution from third-party investors to TRIP Holdings				$ 49.6