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Chapter 11 Proceedings - Additional Information (Details) $ in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Feb. 25, 2021 USD ($) claim | Dec. 31, 2020 USD ($) | Nov. 13, 2020
Debt Instrument [Line Items] |  |  |
Debtor-in-possession financing, percentage of lenders involved |  |  | 95.00%
Holders of an allowed general unsecured claim, percentage of new common stock received |  | 94.00% |
Debtor-in-possession financing, letters of credit outstanding |  | $ 262.5 |
Debtor-in-possession financing, amount arranged |  | 105.0 |
Debtor-in-possession financing, borrowings outstanding |  | 157.5 |
Contractual interest expense |  | $ 15.3 |
Subsequent Event |  |  |
Debt Instrument [Line Items] |  |  |
Number of claims | claim | 2,200 |  |
Claims amount | $ 12,500.0 |  |
6.625% senior unsecured notes due 2023 | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Stated interest rate |  | 6.625% |
6.000% senior unsecured notes due 2024 | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Stated interest rate |  | 6.00% |
6.375% senior unsecured notes due 2025 | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Stated interest rate |  | 6.375% |
6.375% senior unsecured notes due 2026 | Senior notes |  |  |
Debt Instrument [Line Items] |  |  |
Stated interest rate |  | 6.375% |

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