Emergence from the Chapter 11 Cases and Fresh Start Reporting - Summary of Provisions (Details) - Successor - Effect of Plan	Apr. 01, 2017 USD ($) shares
Fresh-Start Adjustment [Line Items]
Stock and warrants issued, value	$ 750,000,000
Warrants issued (in shares)	6,200,000
First Lien Senior Secured Notes \| Senior Notes
Fresh-Start Adjustment [Line Items]
Principal amount	1,000,000,000.0
First LIen Credit Facility \| Line of Credit
Fresh-Start Adjustment [Line Items]
Principal amount	950,000,000.0
Series A Preferred Stock
Fresh-Start Adjustment [Line Items]
Preferred stock, value	$ 750,000,000
Preferred stock, shares issued (in shares) \| shares	30,000,000.0
Common Stock
Fresh-Start Adjustment [Line Items]
Stock issued (in shares)	$ 70,900,000

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Equity impact of the value of new stock issued during the period. Includes shares issued in an initial public offering or a secondary public offering.

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