Mineral rights at exploration properties acquired in a business combination.

No definition available.

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- Definition

Net book value of coal reserves.

+ References

No definition available.

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- Definition

Coal reserves not subject to depletion.

+ References

No definition available.

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- Definition

Land and coal interests.

+ References

No definition available.

+ Details

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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
-Name Accounting Standards Codification
-Topic 210
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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

Amount before accumulated depreciation of building structures held for productive use including addition, improvement, or renovation to the structure, including, but not limited to, interior masonry, interior flooring, electrical, and plumbing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Paragraph 4
-Subparagraph (f)
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- Definition

Amount before accumulated depreciation of tangible personal property used to produce goods and services, including, but is not limited to, tools, dies and molds, computer and office equipment.

+ References

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- Definition

Carrying amount at the balance sheet date of mineral rights, or rights to extract a mineral from the earth or to receive payment in the form of a royalty for the extraction of minerals, net of amortization.

+ References

No definition available.

+ Details

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- 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.

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- Definition

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
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Property, Plant, Equipment and Mine Development (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Successor
Property, Plant, Equipment and Mine Development[Line Items]
Land and coal interests	$ 3,890.5
Buildings and improvements	470.6
Machinery and equipment	1,149.3
Less: accumulated depreciation, depletion and amortization	(398.5)
Property, plant, equipment and mine development, net	5,111.9
Coal reserves	3,000.0
Coal reserves not subject to depletion	200.0
Acquired interest in mineral rights	100.0
Successor \| Mining Properties and Mineral Rights [Member]
Property, Plant, Equipment and Mine Development[Line Items]
Mineral rights and advanced royalties	2,000.0
Successor \| Coal reserves held by fee ownership [Member]
Property, Plant, Equipment and Mine Development[Line Items]
Coal reserves	$ 1,000.0
Predecessor
Property, Plant, Equipment and Mine Development[Line Items]
Land and coal interests		$ 10,330.8
Buildings and improvements		1,507.6
Machinery and equipment		2,130.2
Less: accumulated depreciation, depletion and amortization		(5,191.9)
Property, plant, equipment and mine development, net		8,776.7	$ 9,258.5
Coal reserves		5,500.0
Coal reserves not subject to depletion		1,600.0
Acquired interest in mineral rights		1,200.0
Predecessor \| Mining Properties and Mineral Rights [Member]
Property, Plant, Equipment and Mine Development[Line Items]
Mineral rights and advanced royalties		4,400.0
Predecessor \| Coal reserves held by fee ownership [Member]
Property, Plant, Equipment and Mine Development[Line Items]
Coal reserves		$ 1,100.0