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Derivatives and Fair Value Measurements Fair Value of Long-term Debt (Details) - Successor $ in Millions	Dec. 31, 2017 USD ($)
Estimate of Fair Value Measurement [Member]
Fair Value of Debt [Line Items]
Debt Instrument, Fair Value Disclosure	$ 1,547.4
Carrying Value Measurement [Member]
Fair Value of Debt [Line Items]
Debt Instrument, Fair Value Disclosure	$ 1,460.8

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- Definition

[Line Items] for Fair Value of Debt [Table]

+ References

No definition available.

+ Details

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

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