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- Definition

Derecognition of Membership Interest, Net Assets

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- Definition

Equity Method Investment, Joint Venture Majority Ownership Percentage

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- Definition

Gain on Divestiture of Partially-owned Leasing Subsidiary

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No definition available.

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- Definition

Amount of transaction cost incurred to effect business combination. Excludes separately recognized transaction and indirect cost.

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- Definition

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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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Percentage of ownership of equity interest excluding interest in entity that is consolidated and equity method investee.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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- Definition

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

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No definition available.

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- Definition

The amount of investments that an Entity acquires in a noncash (or part noncash) acquisition. Noncash is defined as information about all investing and financing activities of an enterprise during a period that affect recognized assets or liabilities but that do not result in cash receipts or cash payments in the period. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The amount of the reduction or elimination during the period of a noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest.

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- Definition

The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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Partially-Owned Subsidiaries - Narrative (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2026	Jun. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Mar. 31, 2026
Noncontrolling Interest [Line Items]
Gain on Divestiture of Partially-owned Leasing Subsidiary	$ 0.0		$ 0.0	$ 131.6	$ 0.0
Noncash or Part Noncash Acquisition, Investments Acquired					0.0
Noncontrolling Interest, Decrease from Deconsolidation		$ 64.3			$ 0.0
NP SPE Holdings LP
Noncontrolling Interest [Line Items]
Equity Method Investment, Ownership Percentage	11.20%			11.20%
Noncash or Part Noncash Acquisition, Investments Acquired				$ 112.9
Equity Method Investment, JV Majority Ownership Percentage	88.80%			88.80%
Signal Rail Holdings LLC
Noncontrolling Interest [Line Items]
Equity Method Investment, Ownership Percentage	11.50%			11.50%
Equity Method Investment, JV Majority Ownership Percentage	88.50%			88.50%
RIV Partnerships
Noncontrolling Interest [Line Items]
Equity Method Investments	$ 121.1			$ 121.1
Touax Texmaco Railcar Leasing Private Limited
Noncontrolling Interest [Line Items]
Equity Method Investment, Ownership Percentage	32.00%			32.00%
Equity Method Investments	$ 37.0			$ 37.0
Payments to Acquire Interest in Joint Venture				37.6
Business Combination, Transaction Cost, Excluding Separately Recognized Transaction		$ 1.6
TRIP Holdings [Member] \| Leasing & Services
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent						42.56%
Noncontrolling Interest, Decrease from Deconsolidation				64.3
Triumph Rail Holdings LLC \| Leasing & Services
Noncontrolling Interest [Line Items]
Equity Ownership, Excluding Consolidated Entity and Equity Method Investee, Percentage						0.20%
Tribute Rail LLC
Noncontrolling Interest [Line Items]
Derecognition of Membership Interest, Net Assets				$ 50.0
Partially-owned subsidiaries \| Rail Products Group [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	51.00%			51.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	49.00%			49.00%
Carrying Value of Investment In Partially-Owned Consolidated Subsidiary	$ 2.7			$ 2.7