Break Fees On Terminated Asset Sales

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- Definition

Derivative Instruments Not Designated as Hedging Instruments, Unrealized Gain (Loss), Net

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- Definition

Fresh Start Adjustment, Fair Value Adjustment

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No definition available.

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- Definition

Fresh-Start Adjustment, Revaluation of Inventory

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No definition available.

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- Definition

Mark-to-Market Adjustment on Pension and Postretirement Plans, Net

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No definition available.

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- Definition

Segment Reporting Information Adjusted Earning Before Interest Taxes Depreciation And Amortization.

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No definition available.

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- Definition

Selling and Administrative expenses related to debt restructuring

+ References

No definition available.

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- Definition

Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

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-Name Accounting Standards Codification
-Topic 410
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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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- Definition

The difference between the book value and the sale price of agreements to purchase or sell mineral resources, energy, and agricultural products at some future point. This element refers to the gain (loss) included in earnings and not to the cash proceeds.

+ References

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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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- Definition

Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest.

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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Name Accounting Standards Codification
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- Definition

The net amount of operating interest income (expense).

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Amount before accretion (amortization) of purchase discount (premium) of interest income on nonoperating securities.

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-Name Accounting Standards Codification
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- Definition

Total amount of reorganization items.

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Amount, after cash payment, of expenses associated with exit or disposal activities pursuant to an authorized plan and expenses resulting from the write-down of assets. Excludes expenses related to a business combination, a discontinued operation or an asset retirement obligation.

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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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No definition available.

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Segment and Geographic Information Reconciliation of Consolidated Income (Loss), Net of Income Taxes to Adjusted EBITDA (Details) - USD ($) $ in Millions		3 Months Ended									9 Months Ended	12 Months Ended
	Apr. 01, 2017	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Apr. 01, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Predecessor
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (loss) from continuing operations, net of tax, including portion attributable to noncontrolling interest	$ (319.8)				$ (195.5)	$ 124.3	$ (175.2)	$ (97.7)	$ (223.2)	$ (167.7)			$ (663.8)	$ (1,783.2)
Depreciation, depletion and amortization					119.9								465.4	572.2
Asset Retirement Obligation, Accretion Expense					14.6								41.8	45.5
Selling and Administrative expenses related to debt restructuring					0.0								21.5	0.0
Mark-to-Market Adjustment on Pension and Postretirement Plans, Net					0.0								0.0	0.0
Restructuring Costs and Asset Impairment Charges					30.5	30.5	230.7			$ 17.2			247.9	1,277.8
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount					(5.2)								(7.5)	3.9
Interest Income (Expense), Net					32.9								298.6	465.4
Loss on early debt extinguishment					0.0		(29.5)						29.5	67.8
Interest income					(2.7)								(5.7)	(7.7)
Derivative Instruments Not Designated as Hedging Instruments, Unrealized Gain (Loss), Net					16.6								(39.8)	2.2
Fresh-Start Adjustment, Revaluation of Inventory					0.0								0.0	0.0
Fresh Start Adjustment, Fair Value Adjustment					0.0								0.0	0.0
Reorganization Items	$ 585.8				627.2	$ 41.4	$ 33.9	$ 29.7	$ 95.4				159.0	0.0
Income Tax (Benefit) Expense					(263.8)								(94.5)	(207.1)
Segment Reporting Information Adjusted Earning Before Interest Taxes Depreciation And Amortization					341.3								532.0	432.4
Break Fees On Terminated Asset Sales					0.0								0.0	0.0
Gain (Loss) on Sale of Commodity Contracts					0.0								0.0	0.0
Successor
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Income (loss) from continuing operations, net of tax, including portion attributable to noncontrolling interest		$ 378.0	$ 233.7	$ 101.4							$ 713.1
Depreciation, depletion and amortization											521.6
Asset Retirement Obligation, Accretion Expense											41.2
Selling and Administrative expenses related to debt restructuring											0.0
Mark-to-Market Adjustment on Pension and Postretirement Plans, Net		45.2									(45.2)
Restructuring Costs and Asset Impairment Charges											0.0
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount											(17.3)	$ (2,400.0)
Interest Income (Expense), Net											119.7
Loss on early debt extinguishment		(8.0)	$ (12.9)								20.9
Interest income											(5.6)
Derivative Instruments Not Designated as Hedging Instruments, Unrealized Gain (Loss), Net											(23.0)
Fresh-Start Adjustment, Revaluation of Inventory											67.3
Fresh Start Adjustment, Fair Value Adjustment											(22.5)
Reorganization Items											0.0
Income Tax (Benefit) Expense											(161.0)
Segment Reporting Information Adjusted Earning Before Interest Taxes Depreciation And Amortization											1,145.3
Break Fees On Terminated Asset Sales											28.0
Gain (Loss) on Sale of Commodity Contracts											(1.5)
Springfield Reclamation Liability [Member] \| Predecessor
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gain (Loss) on Sale of Properties					0.0								0.0	0.0
Springfield Reclamation Liability [Member] \| Successor
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gain (Loss) on Sale of Properties		31.2									(31.2)
Burton Mine [Member] \| Predecessor
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gain (Loss) on Sale of Properties					$ 0.0								$ 0.0	$ 0.0
Burton Mine [Member] \| Successor
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Gain (Loss) on Sale of Properties		$ 52.2									$ (52.2)