Emergence from Voluntary Reorganization under Chapter 11 - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	2 Months Ended
Nov. 19, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Issued of common stock (in shares)	65,000,000
Warrants to purchase of number of shares (in shares)	1,621,622
Warrant exercise price (in usd per share)	$ 94.57
Aggregate principal amount arranged	$ 20.6
Contractual interest expense	$ 15.6
Number of shares available for grant (in shares)		16,050,000
Long Term Incentive Plan (LTIP)
Debt Instrument [Line Items]
Number of shares available for grant (in shares)	2,402,402	2,793,360
Successor Board of Directors
Debt Instrument [Line Items]
Warrants to purchase of number of shares (in shares)	1,621,622
Senior unsecured notes \| Successor Board of Directors
Debt Instrument [Line Items]
Issued of common stock (in shares)	20,000,000
6.50% senior unsecured notes due November 1, 2021 \| Senior unsecured notes
Debt Instrument [Line Items]
Debt stated interest rate (percent)	6.50%	6.50%
6.875% senior unsecured notes due March 15, 2022 \| Senior unsecured notes
Debt Instrument [Line Items]
Debt stated interest rate (percent)	6.875%
6.875% senior unsecured notes due January 15, 2023 \| Senior unsecured notes
Debt Instrument [Line Items]
Debt stated interest rate (percent)	6.875%
6.25% senior unsecured notes due May 1, 2026 \| Senior unsecured notes
Debt Instrument [Line Items]
Debt stated interest rate (percent)	6.25%	6.25%
2.625% senior unsecured convertible notes due September 15, 2023 \| Senior unsecured notes
Debt Instrument [Line Items]
Debt stated interest rate (percent)	2.625%	2.625%
Exit Facility \| Line of credit \| Revolving credit facility
Debt Instrument [Line Items]
Aggregate principal amount arranged		$ 1,500.0
Initial financing available to the borrower	$ 575.0

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

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The amount of contractual interest expense on prepetition liabilities not included in the statement of operations.

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

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Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

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