Assets Held For Sale Assets Held For Sale (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
Asset impairment	$ 0.0	$ (0.1)
Assets Held-for-sale, Long Lived, Fair Value Disclosure	70.6		$ 106.0
Portfolio Proceeds	98.4	176.8
Disposition gains on owned assets	20.0	37.9
Portfolio Management [Member]
Segment Reporting Information [Line Items]
Asset impairment	0.0	0.0
Assets Held-for-sale, Long Lived, Fair Value Disclosure	69.6		103.4
Portfolio Proceeds	37.6
Disposition gains on owned assets	$ 2.4	$ 2.0
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	100.00%

Disposition gains are sales of operating assets

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- Definition

Portfolio proceeds.

+ References

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
-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

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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

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- Definition

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

+ References

No definition available.

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