v3.26.1

Partially-Owned Subsidiaries - Narrative (Details) $ in Millions	3 Months Ended
	Jun. 30, 2026 USD ($)	Apr. 09, 2026	Mar. 31, 2026 USD ($) board_member
Subsequent Event
Noncontrolling Interest [Line Items]
Gain on Divestiture of Partially-owned Leasing Subsidiary	$ 130.0
Signal Rail Holdings LLC
Noncontrolling Interest [Line Items]
Equity Method Investment, JV Majority Ownership Percentage			88.30%
Equity Method Investment, Ownership Percentage			11.70%
Equity Method Investments			$ 12.7
NP SPE Holdings LP \| Subsequent Event
Noncontrolling Interest [Line Items]
Equity Method Investment, Ownership Percentage		11.20%
Partially-owned subsidiaries
Noncontrolling Interest [Line Items]
Parent Company Guarantees			$ 0.0
Leasing & Services \| Partially-owned subsidiaries
Noncontrolling Interest [Line Items]
Number of Board Members \| board_member			7
Number of Board Members of Subsidiary, Designated by Parent \| board_member			2
Partially-owned subsidiaries \| Rail Products Group [Member]
Noncontrolling Interest [Line Items]
Carrying Value of Investment In Partially-Owned Consolidated Subsidiary			$ 2.7
Noncontrolling Interest, Ownership Percentage by Parent			51.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners			49.00%
TRIP Holdings [Member] \| Leasing & Services
Noncontrolling Interest [Line Items]
Carrying Value of Investment In Partially-Owned Consolidated Subsidiary			$ 35.4
Noncontrolling Interest, Ownership Percentage by Parent			42.56%
Triumph Rail Holdings LLC \| Leasing & Services
Noncontrolling Interest [Line Items]
Equity Ownership, Excluding Consolidated Entity and Equity Method Investee, Percentage			0.20%

Carrying Value of Investment In Partially-Owned Consolidated Subsidiary

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Equity Method Investment, Joint Venture Majority Ownership Percentage

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Gain on Divestiture of Partially-owned Leasing Subsidiary

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Number of Board Members

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Parent Company Guarantees

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

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TRINITY INDUSTRIES INC 10-Q