Predecessor Company Share-Based Compensation Expense and Cash Flows (Details) - Predecessor - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Apr. 01, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-Based Compensation Expense and Cash Flows (Line Items)
Share-based Compensation, Total	$ 1.9	$ 12.8	$ 28.2
Employee Service Share-based Compensation, Tax Benefit from Compensation Expense	0.0	0.0	0.0
Share Based Compensation Expense Net of Tax	1.9	12.8	28.2
Proceeds from Stock Options Exercised	0.0	0.0	3.4
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	0.0	0.0	0.0
Equity Award
Share-Based Compensation Expense and Cash Flows (Line Items)
Share-based compensation	1.9	11.3	26.2
Other Liabilities [Member]
Share-Based Compensation Expense and Cash Flows (Line Items)
Share-based compensation	$ 0.0	$ 1.5	$ 2.0

Share Based Compensation Expense Net of Tax.

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- Definition

The aggregate amount of noncash, equity- and liability- based employee renumeration.

+ References

No definition available.

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- Definition

Amount of increase in additional paid in capital (APIC) resulting from a tax benefit associated with share-based compensation plan other than an employee stock ownership plan (ESOP). Includes, but is not limited to, excess tax benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 740
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=79981250&loc=d3e23524-113945

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=SL79508275-113901

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- Definition

The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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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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