Unaudited Condensed Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions		3 Months Ended	6 Months Ended
Apr. 01, 2017	Jun. 30, 2018	Jun. 30, 2017	Apr. 01, 2017	Jun. 30, 2018
Successor
Reclassification for realized losses on cash flow hedges included in net income (loss), tax provision		$ 0.0	$ 0.0		$ 0.0
Postretirement plans and workers' compensation obligations, tax provision		$ 0.0	$ 0.0		$ 0.0
Predecessor
Reclassification for realized losses on cash flow hedges included in net income (loss), tax provision	$ 0.0			$ 9.1
Postretirement plans and workers' compensation obligations, tax provision	$ 0.0			$ 2.5

Amount, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e640-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 19
-URI http://asc.fasb.org/extlink&oid=96868048&loc=SL4569616-111683

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i-k)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

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