Railcars in Flammable Service

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Fair value portion of assets classified as held for sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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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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 sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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Asset Impairments and Assets Held for Sale (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2015
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$ 4,500,000	$ 89,500,000
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property	52,500,000	52,900,000	$ 99,700,000
Asset Impairment Charges	8,600,000	38,500,000	33,900,000
Equity Method Investment, Net Sales Proceeds	2,300,000	1,000,000	24,700,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Number of railars		400
Cardinal Marine [Domain]
Noncontrolling Interest, Ownership Percentage by Parent				50.00%
Asset Impairment Charges			19,000,000
Cardinal Marine [Member]
Asset Impairment Charges	0	0	19,000,000
Rail North America [Member]
Assets Held-for-sale, Long Lived, Fair Value Disclosure	4,500,000	43,900,000
Asset Impairment Charges	4,600,000	31,200,000	2,500,000
Rail International [Member]
Asset Impairment Charges	300,000	600,000	400,000
Portfolio Management [Member]
Assets Held-for-sale, Long Lived, Fair Value Disclosure	0	45,600,000
Gain (Loss) on Disposition of Assets	1,800,000	5,200,000	21,600,000
Asset Impairment Charges	3,700,000	6,700,000	31,000,000
Portfolio Management [Member] \| Cardinal Marine [Domain]
Asset Impairment Charges			19,000,000
Fair Value, Measurements, Nonrecurring [Member] \| Fair Value, Inputs, Level 3 [Member]
Number of railars		2,400
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member]
Asset Impairment Charges	8,600,000	2,000,000	3,100,000
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Rail North America [Member]
Asset Impairment Charges		5,800,000
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Nordic Vessels [Member] \| Portfolio Management [Member]
Asset Impairment Charges		6,700,000	30,800,000
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| InflammableRailcars [Member] \| Rail North America [Member]
Asset Impairment Charges	0	$ 29,800,000	0
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Marine vessels [Member] \| Portfolio Management [Member]
Asset Impairment Charges	$ 0		$ 30,800,000