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

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-Name Accounting Standards Codification
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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.

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Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
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Fair Value Measurements (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Predecessor [Member] \| Senior Notes [Member] \| Senior Notes Due 2017 [Member]
Fair value of senior notes
Fair value of senior notes		$ 23.0
Carrying value of senior notes		250.0
Predecessor [Member] \| Senior Notes [Member] \| Senior Notes Due 2020 [Member]
Fair value of senior notes
Fair value of senior notes		21.4
Carrying value of senior notes		225.0
Predecessor [Member] \| Senior Notes [Member] \| Senior Notes Due 2022 [Member]
Fair value of senior notes
Fair value of senior notes		34.5
Carrying value of senior notes		$ 400.0
Other Contract [Member] \| Fair Value, Measurements, Recurring [Member] \| Successor [Member]
Debt Instrument [Line Items]
Derivative Asset	$ 0.4
Fair Value, Inputs, Level 1 [Member] \| Other Contract [Member] \| Fair Value, Measurements, Recurring [Member] \| Successor [Member]
Debt Instrument [Line Items]
Derivative Asset	0.0
Fair Value, Inputs, Level 2 [Member] \| Other Contract [Member] \| Fair Value, Measurements, Recurring [Member] \| Successor [Member]
Debt Instrument [Line Items]
Derivative Asset	0.4
Fair Value, Inputs, Level 3 [Member] \| Other Contract [Member] \| Fair Value, Measurements, Recurring [Member] \| Successor [Member]
Debt Instrument [Line Items]
Derivative Asset	$ 0.0