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v3.21.1

Senior Secured Notes (Details) | 3 Months Ended |
--- | --- | ---
Mar. 31, 2021 USD ($) $ / shares | Mar. 31, 2020 USD ($) | Dec. 31, 2020 USD ($)
Senior Notes [Line Items] |  |  |
Secured Long-term Debt, Noncurrent | $ 464,222,000 |  | $ 460,656,000
1.50% Senior Secured Convertible Notes Due 2021 [Member] |  |  |
Senior Notes [Line Items] |  |  |
Senior Notes, interest rate, stated percentage | 1.50% |  | 1.50%
Senior Notes, Principal amount | $ 65,485,000 |  | $ 65,485,000
Senior Secured Notes, Unamortized Debt Discount | 914,000 |  | 1,828,000
Senior Notes, unamortized deferred financing costs | 87,000 |  | 175,000
Secured Long-term Debt, Noncurrent | $ 64,484,000 |  | $ 63,482,000
Debt Instrument, Convertible, Conversion Ratio | 24.6914 |  |
Debt Instrument, Principal Amount of Note | $ 1,000 |  |
Senior Convertible Notes, conversion price | $ / shares | $ 40.50 |  |
Interest Expense, Debt | $ 1,200,000 | $ 2,900,000 |
10.0% Senior Secured Notes due 2025 [Member] |  |  |
Senior Notes [Line Items] |  |  |
Senior Notes, interest rate, stated percentage | 10.00% |  | 10.00%
Senior Notes, Principal amount | $ 446,675,000 |  | $ 446,675,000
Senior Secured Notes, Unamortized Debt Discount | 36,085,000 |  | 37,943,000
Senior Notes, unamortized deferred financing costs | 10,852,000 |  | 11,558,000
Secured Long-term Debt, Noncurrent | 399,738,000 |  | 397,174,000
Senior Secured Notes [Member] |  |  |
Senior Notes [Line Items] |  |  |
Senior Notes, Principal amount | 512,160,000 |  | 512,160,000
Senior Secured Notes, Unamortized Debt Discount | 36,999,000 |  | 39,771,000
Senior Notes, unamortized deferred financing costs | $ 10,939,000 |  | $ 11,733,000

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