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Plan of Reorganization, Terms of Plan, Holders of Allowed Claims, Percentage of Common Stock Outstanding Upon Reorganization

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Plan of Reorganization, Terms of Plan, Holders of Allowed Claims, Pro Rata Amount of Cash to Settle Claim

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- Definition

Postconfirmation Credit Facility Option

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Postconfirmation Credit Facility, Prepayment Fee

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- Definition

Potential Postconfirmation Convertible Debt

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Amount of bankruptcy claim filed with bankruptcy court.

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The aggregate number of claims filed with the bankruptcy court.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Carrying value as of the balance sheet date of loans from a bank with maturities initially due after one year or beyond the operating cycle if longer, excluding current portion.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Including the current and noncurrent portions, 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). Senior note holders are paid off in full before any payments are made to junior note holders.

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Description of Business, Interim Financial Data and Basis of Presentation (Current Bankruptcy Proceedings and Liquidity and Going Concern) (Details)		3 Months Ended		12 Months Ended
	Dec. 09, 2017 USD ($)	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($) claim	Oct. 30, 2017 USD ($)	Dec. 23, 2013 USD ($)	May 13, 2011 USD ($)
Debt Instrument [Line Items]
Potential postconfirmation convertible debt				$ 1,000,000,000
Postconfirmation credit facility option	$ 50,000,000
Number of claims filed \| claim				1,400
Amount of claims filed				$ 2,600,000,000
Cash and cash equivalents		$ 120,122,000		$ 102,891,000
Net cash provided by operating activities		48,372,000	$ 19,425,000
Senior notes		$ 610,000,000.0					$ 610,000,000.0
Term Loan
Debt Instrument [Line Items]
Holders of allowed claims pro-rata amount of cash to settle claims	$ 1,300,000,000
Holders of allowed claims percentage of common stock outstanding upon reorganization	83.50%
Senior Notes at 7.75%
Debt Instrument [Line Items]
Holders of allowed claims percentage of common stock outstanding upon reorganization	16.50%
Interest rate	7.75%
New First Lien Debt - Option 1
Debt Instrument [Line Items]
Basis spread on variable rate	4.50%
New First Lien Debt - Option 2
Debt Instrument [Line Items]
Basis spread on variable rate	3.50%
New First Lien Debt
Debt Instrument [Line Items]
Postconfirmation credit facility, prepayment fee	1.00%
Minimum \| New First Lien Debt - Option 1
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Minimum \| New First Lien Debt - Option 2
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
7.75% senior notes
Debt Instrument [Line Items]
Interest rate		7.75%		7.75%			7.75%
Interest expense forgone					$ 23,600,000
Term loan \| Term Loan
Debt Instrument [Line Items]
Loans payable		$ 1,700,000,000
Revolving Credit Facility \| Amended and Restated Credit Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity						$ 200,000,000.0