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- Definition

Portfolio proceeds.

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No definition available.

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- Definition

Railcars in Flammable Service

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No definition available.

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- Definition

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
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-Name Accounting Standards Codification
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- Definition

Fair value portion of assets classified as held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Asset Impairments and Assets Held for Sale (Details)	3 Months Ended		12 Months Ended
Asset Impairments and Assets Held for Sale (Details)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) Vessel	Dec. 31, 2014 USD ($)
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$ 106,000,000		$ 89,500,000	$ 106,000,000
Portfolio proceeds and other			223,700,000	482,200,000	$ 264,000,000
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property			52,900,000	99,700,000	79,300,000
Asset Impairment Charges			38,500,000	33,900,000	1,300,000
Equity Method Investment, Net Sales Proceeds			1,000,000	$ 24,700,000	19,400,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member]
Number of railars			400
Cardinal Marine [Member]
Noncontrolling Interest, Ownership Percentage by Parent	50.00%			50.00%
Asset Impairment Charges			0	$ 19,000,000	0
Rail North America [Member]
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$ 2,600,000		43,900,000	2,600,000
Asset Impairment Charges			31,200,000	2,500,000	700,000
Rail International [Member]
Asset Impairment Charges			600,000	400,000	300,000
Portfolio Management [Member]
Assets Held-for-sale, Long Lived, Fair Value Disclosure	103,400,000		45,600,000	103,400,000
Gain (Loss) on Disposition of Assets			5,200,000	21,600,000
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property		$ (26,600,000)
Asset Impairment Charges			6,700,000	$ 31,000,000	(100,000)
gmt_Number of Sold Vessels \| Vessel				6
Marine vessels [Member] \| Portfolio Management [Member]
Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property	$ (9,000,000)
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] \| 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				$ 30,800,000
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| InflammableRailcars [Member]
Asset Impairment Charges			2,000,000	3,100,000	1,300,000
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| InflammableRailcars [Member] \| Rail North America [Member]
Asset Impairment Charges			29,800,000	$ 0	0
Fair Value, Measurements, Nonrecurring [Member] \| Changes Measurement [Member] \| Fair Value, Inputs, Level 3 [Member] \| Marine vessels [Member] \| Portfolio Management [Member]
Asset Impairment Charges			$ 6,700,000		$ 0