Properties, Plants and Equipment, Net (Details Textual) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Properties Plants and Equipment, Net (Textual) [Abstract]
Accumulated depreciation	$ 703.2	$ 619.3
Properties, plants and equipment, net	1,593.4	1,480.0
Gross investment, at cost	2,296.6	2,099.3
Coke and energy plant, machinery and equipment
Properties Plants and Equipment, Net (Textual) [Abstract]
Coke and energy plant, machinery and equipment	1,278.3	1,155.1
Accumulated depreciation	371.7	262.4
Gross investment, at cost	1,715.3	1,676.3
Mining
Properties Plants and Equipment, Net (Textual) [Abstract]
Properties, plants and equipment, net	13.1	22.8
Gross investment, at cost	148.4	151.5
Construction-in-progress
Properties Plants and Equipment, Net (Textual) [Abstract]
Gross investment, at cost	106.1	$ 65.6
Construction-in-progress \| Convent Marine Terminal
Properties Plants and Equipment, Net (Textual) [Abstract]
Gross investment, at cost	$ 37.3

-- None. No documentation exists for this element. --

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The cash outflow for acquisition of machinery and equipment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
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-Publisher SEC
-Name Regulation S-X (SX)
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-Section 02
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