Net Book Value of Unpledged Equipment.

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Railcars acquired in subsequent event

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

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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Amount of assets pledged to secure a debt instrument.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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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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Railcar Leasing and Management Services Group - Narrative (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($)	Jan. 14, 2019 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2009 USD ($)
Segment Reporting Information [Line Items]
Assets	$ 7,989.2		$ 9,543.2
Property, plant, and equipment, net	6,334.4		5,557.8
Railcar Leasing and Management Services Group
Segment Reporting Information [Line Items]
Assets	7,096.0		6,267.9
Railcar Leasing and Management Services Group \| Property lease guarantee
Segment Reporting Information [Line Items]
Operating lease obligations guaranteed	1.8
Railcar Leasing and Management Services Group \| Capital lease obligations
Segment Reporting Information [Line Items]
Capital lease obligations	0.0		$ 28.3	$ 56.6
Gain (Loss) on Disposition of Assets	$ 12.6
Railcar Leasing and Management Services Group \| Minimum
Segment Reporting Information [Line Items]
Term of leases with third parties	1 year
Railcar Leasing and Management Services Group \| Maximum
Segment Reporting Information [Line Items]
Term of leases with third parties	20 years
Wholly owned qualified subsidiaries for leasing railcars from the Trusts \| Railcar Leasing and Management Services Group \| Railroad transportation equipment leased from independent owner trusts
Segment Reporting Information [Line Items]
Period of railcars leased from the Trusts under operating leases (in years)	22 years
TRL 2012 \| Railcar Leasing and Management Services Group \| Secured debt \| TRL 2012 secured railcar equipment notes
Segment Reporting Information [Line Items]
Net book value pledged as collateral	$ 550.2
TRIP Holdings \| Railcar Leasing and Management Services Group \| Secured debt \| TRIP Master Funding secured railcar equipment notes
Segment Reporting Information [Line Items]
Net book value pledged as collateral	1,264.4
Wholly-owned subsidiaries \| Railcar Leasing and Management Services Group
Segment Reporting Information [Line Items]
Net book value of unpledged equipment	1,459.4
Wholly-owned subsidiaries \| Railcar Leasing and Management Services Group \| Secured debt
Segment Reporting Information [Line Items]
Net book value pledged as collateral	$ 3,440.0
Subsequent event
Segment Reporting Information [Line Items]
Railcars acquired in subsequent event		6,779
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt		$ 218.4