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.

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=68055307&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=98514028&loc=d3e3602-108585

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The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 15
-URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2611-110228

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)
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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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Asset Impairment (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended	9 Months Ended	12 Months Ended
Asset Impairment (Details) - USD ($) $ in Millions	Apr. 01, 2017	Sep. 30, 2016	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2016
Asset Impairment
Asset impairment					$ 247.9
Predecessor
Asset Impairment
Asset impairment	$ 30.5	$ 0.0		$ 17.2
Terminated Coal Lease Contracts \| Predecessor
Asset Impairment
Asset impairment	$ 30.5
Queensland, Australia \| Predecessor
Asset Impairment
Write down of certain targeted divestiture assets			$ 17.2