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Inventories Details Textuals (Details) - Reserve for materials and supplies [Member] - USD ($) $ in Millions	Dec. 31, 2017	Apr. 01, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Successor
Valuation and Qualifying Accounts Disclosure [Line Items]
Materials and supplies reserves	$ 0.6	$ 0.0
Predecessor
Valuation and Qualifying Accounts Disclosure [Line Items]
Materials and supplies reserves		$ 0.0	$ 5.6	$ 4.7	$ 4.6

X

- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

+ Details

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X

- 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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