(Treatment of Claims and New First Lien Debt Facility) (Details)	Oct. 05, 2016 USD ($) $ / shares
Fresh-Start Adjustment [Line Items]
Holders of allowed claims pro-rata amount of cash to settle claims	$ 144,800,000.0
Holders of allowed claims amount of cash to settle claims	$ 30,000,000
Holders of allowed claims percentage of common stock outstanding upon reorganization	94.00%
Holders of allowed claims warrant exercise period	7 years
Holders of allowed claims total equity value of common stock	$ 1,425,000,000
Exercise price of warrants (in usd per share) \| $ / shares	$ 57
Holders of allowed claims percentage of common stock outstanding pursuant to incentive plan upon reorganization	10.00%
Unsecured note holders pro rata amount of cash to settle claims	$ 22,636,000
Unsecured note holders pro rata amount of cash in lieu of warrants	$ 25,000,000
Unsecured note holders percentage of common stock outstanding upon reorganization	6.00%
Other general holders pro rata amount of cash to settle claims	$ 7,364,000
Other general holders professional expenses retained by claims committee	200,000
New first lien debt facility \| Senior notes
Fresh-Start Adjustment [Line Items]
Amount of debt instrument	$ 326,500,000.0
Class A Common Stock
Fresh-Start Adjustment [Line Items]
Holders of allowed claims percentage of common stock outstanding upon reorganization	12.00%

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Exercise price per share or per unit of warrants or rights outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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