Disposition gains are sales of operating assets

No definition available.

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- Definition

gmt_Number of Sold Vessels

+ References

No definition available.

+ Details

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- Definition

Portfolio proceeds.

+ References

No definition available.

+ Details

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=51824106&loc=d3e2420-110228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

+ Details

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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
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19190-110258

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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Assets Held For Sale Assets Held For Sale (Details) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2016 USD ($)	Sep. 30, 2015 Vessel	Jun. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2015 USD ($)	Dec. 31, 2015 USD ($)
Segment Reporting Information [Line Items]
Asset impairment	$ (1.8)		$ 0.0	$ (1.8)	$ (0.1)
Assets Held-for-sale, Long Lived, Fair Value Disclosure	65.0			65.0		$ 106.0
Portfolio Proceeds				123.8	211.5
Disposition gains on owned assets	5.1		5.1	25.1	43.0
Portfolio Management [Member]
Segment Reporting Information [Line Items]
gmt_Number of Sold Vessels \| Vessel		6
Asset impairment	(1.8)		0.0	(1.8)	0.0
Assets Held-for-sale, Long Lived, Fair Value Disclosure	63.8			63.8		$ 103.4
Portfolio Proceeds				46.5
Disposition gains on owned assets	$ 2.1		$ 0.1	4.5	$ 2.1
Nordic Vessels [Member] \| Portfolio Management [Member]
Segment Reporting Information [Line Items]
Asset impairment				$ 0.0
Cardinal Marine [Domain]
Segment Reporting Information [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent		50.00%