Fresh Start Accounting (Narrative) (Details) - USD ($)	Jun. 04, 2018	Jun. 03, 2018
Fresh-Start Adjustment [Line Items]
Estimated enterprise value	$ 1,675,000,000
Short-term debt	13,000,000
Term Loan	$ 1,287,000,000
Fair value of debt as a percentage of par value (percent)	100.00%
Debt issuance costs	$ 18,000,000
Asset write off	2,200,000
Deferred tax liabilities	50,400,000
Deferred tax liability, subject to compromise	50,437	$ 237,247,000
Goodwill adjustment	(135,214,000)
Minimum
Fresh-Start Adjustment [Line Items]
Estimated enterprise value	1,500,000,000
Maximum
Fresh-Start Adjustment [Line Items]
Estimated enterprise value	1,700,000,000
Fresh Start Adjustments
Fresh-Start Adjustment [Line Items]
Goodwill adjustment	(135,214,000)
Term Loan	18,000,000
Intangible assets fair value adjustment	147,900,000
Term Loan \| Reorganization Adjustments
Fresh-Start Adjustment [Line Items]
Prepaid expenses and other current assets	$ 17,800,000

Debtor Reorganization Items, Fair Value Of Debt, Percent Of Par Value

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