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v3.21.1

Subsequent Events (Details) - USD ($) | Apr. 16, 2021 | Apr. 14, 2021 | Apr. 09, 2021 | Mar. 31, 2021 | Dec. 31, 2020 | Jul. 01, 2020
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Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Collective bargaining agreement, term | 5 years |  |  |  |  |
Senior Secured Notes Due June 01, 2025 [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Debt instrument, tender premium |  |  |  | $ 14,600,000 |  |
Long-term Debt [Member] | Convertible Senior Note Due 2028 [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Face amount |  |  | $ 86,300,000 |  |  |
Percentage of aggregate principal amount issued |  |  | 100.00% |  |  |
Interest rate, cash percentage |  |  | 2.75% |  |  |
Long-term Debt [Member] | Senior Secured Notes Due 2028 [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Face amount |  | $ 250,000,000.0 |  |  |  |
Stated interest rate, percentage |  | 7.50% |  |  |  |
Debt instrument, repurchased face amount |  | $ 195,900,000 |  |  |  |
Long-term Debt [Member] | Senior Secured Notes Due June 01, 2025 [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Face amount |  |  |  |  |  | $ 250,000,000.0
Stated interest rate, percentage |  |  |  | 12.00% |  | 12.00%
Debt discount |  |  |  | $ 2,200,000 | $ 2,300,000 |
Long-term Debt [Member] | Senior Secured Notes Due June 01, 2025 [Member] | Subsequent Event [Member] |  |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |  |
Face amount |  | $ 250,000,000.0 |  |  |  |
Interest rate, cash percentage |  | 7.50% |  |  |  |
Write off of deferred financing cost |  | $ 4,400,000 |  |  |  |
Debt discount |  | 2,200,000 |  |  |  |
Debt instrument, tender premium |  | $ 14,600,000 |  |  |  |

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