Debtor Reorganization Items, Fresh-Start Adjustment, Increase (Decrease), Stockholders' Equity, before Tax

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- Definition

Debtor Reorganization Items, Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense

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Fresh-Start Adjustment, Reorganization Gain (Loss), Net

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Payments for Reorganization Items, Net

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- Definition

Payments of Reorganization Professional Fees

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- Definition

Amount of net gain (loss) on settlement of other claims for entities in bankruptcy, reported as a reorganization item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64805424&loc=d3e55730-112764

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766

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Amount of interest income on accumulated cash, reported as a reorganization item.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56145-112766

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=64805424&loc=d3e55730-112764

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Amount of reorganization items related to legal and advisory professional fees related to entities in bankruptcy.

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- Definition

Amount of gain (loss) on rejection of leases and other executory contracts, reported as a reorganization item.

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Amount of expense (income) related to reorganization items classified as other.

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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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Total amount of reorganization items.

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Reorganization Items, Net (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended	12 Months Ended
Reorganization Items, Net (Details) - USD ($) $ in Millions	Apr. 01, 2017	Mar. 31, 2018	Apr. 01, 2017	Mar. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2016
Fresh-Start Adjustment [Line Items]
Fresh-Start Adjustment, Reorganization Gain, Net	$ (3,031.2)
Legal and Advisory Professional Fees	336.4
Payments of Reorganization Professional Fees	8.3
Predecessor
Fresh-Start Adjustment [Line Items]
Fresh-Start Adjustment, Reorganization Gain, Net			$ (3,031.2)				$ 0.0
Fresh-Start Adjustment, Increase (Decrease), Stockholders' Equity, before Tax			3,363.1				0.0
Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense			253.9				0.0
Net Loss on Rejection of Leases and Other Executory Contracts			0.0				75.2
Legal and Advisory Professional Fees			42.5				88.4
Gain on Settlement of Other Claims, Net			(0.7)				(1.8)
Interest Income on Accumulated Cash			(0.4)				(1.8)
Other Expense (Income)			0.0				(1.0)
Reorganization Items, net	585.8		627.2	$ 41.4			159.0
Payments for Reorganization Items, Net			$ 45.8				$ 68.1
Predecessor \| Income Tax Effect Related to Predecessor Deferred Tax Liabilities [Member]
Fresh-Start Adjustment [Line Items]
Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense	177.8
Predecessor \| Income Tax Effect Related to AOCI [Member]
Fresh-Start Adjustment [Line Items]
Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense	81.5
Predecessor \| Income Tax Effect Related to Unrecognized Tax Benefits [Member]
Fresh-Start Adjustment [Line Items]
Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense	6.7
Predecessor \| Income Tax Effect Related to Predecessor Deferred Tax Assets of Discontinued Operations [Member]
Fresh-Start Adjustment [Line Items]
Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense	$ (12.1)
Successor
Fresh-Start Adjustment [Line Items]
Fresh-Start Adjustment, Reorganization Gain, Net						$ (12.8)
Fresh-Start Adjustment, Increase (Decrease), Stockholders' Equity, before Tax						0.0
Fresh-Start Income Tax Adjustments, Increase (Decrease) in Expense						0.0
Net Loss on Rejection of Leases and Other Executory Contracts						0.0
Legal and Advisory Professional Fees						0.0
Gain on Settlement of Other Claims, Net						0.0
Interest Income on Accumulated Cash						0.0
Other Expense (Income)						0.0
Reorganization Items, net		$ 12.8			$ 0.0	(12.8)
Payments for Reorganization Items, Net						$ 0.0