Intangible Contract Assets and Liabilities - Narrative (Details) - Fresh Start Reporting - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2017	Apr. 03, 2017
Sales Contracts
Fresh-Start Adjustment [Line Items]
Intangible assets		$ 314.9
Liabilities		58.7
Intangible liabilities		$ 116.2
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization, remainder of 2017	$ 67.2
Amortization, 2018	76.6
Amortization, 2019	37.9
Amortization, 2020	8.8
Amortization, 2021	7.3
Amortization of intangible assets	29.7
Take-Or-Pay Contracts
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
Amortization of intangible liabilities	9.5
Amortization of intangible liabilities, remainder of 2017	12.8
Amortization of intangible liabilities, 2018	27.1
Amortization of intangible liabilities, 2019	18.2
Amortization of intangible liabilities, 2020	9.2
Amortization of intangible liabilities, 2021	$ 4.4

Amortization Of Intangible Liabilities

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Finite-Lived Intangible Liabilities, Amortization Expense, Remainder of Fiscal Year

+ References

No definition available.

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Finite-Lived Intangible Liabilities, Amortization Expense, Year Five

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Finite-Lived Intangible Liabilities, Amortization Expense, Year Four

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Finite-Lived Intangible Liabilities, Amortization Expense, Year Three

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Finite-Lived Intangible Liabilities, Amortization Expense, Year Two

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- Definition

Intangible Liabilities, Gross

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Subparagraph (b)
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-Name Accounting Standards Codification
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

No definition available.

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- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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Amount before accumulated amortization of intangible assets, excluding goodwill.

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No definition available.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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