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Senior Secured Notes (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jul. 01, 2021 | Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020 | Dec. 31, 2020 | Jun. 17, 2020
Senior Notes [Line Items] |  |  |  |  |  |  |
Secured Long-term Debt, Noncurrent |  | $ 405,007 |  | $ 405,007 |  | $ 460,656 |
10.0% Senior Secured Notes due 2025 |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 10.00% |  | 10.00% |  | 10.00% |
Senior Notes, Principal amount |  | $ 446,675 |  | $ 446,675 |  | $ 446,675 | $ 446,700
Senior Secured Notes, Unamortized Debt Discount |  | 32,232 |  | 32,232 |  | 37,943 |
Senior Notes, unamortized deferred financing costs |  | 9,436 |  | 9,436 |  | 11,558 |
Secured Long-term Debt, Noncurrent |  | $ 405,007 |  | $ 405,007 |  | $ 397,174 |
1.50% Senior Secured Convertible Notes Due 2021 |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |
Senior Notes, interest rate, stated percentage |  | 1.50% |  | 1.50% |  | 1.50% |
Senior Notes, Principal amount |  | $ 0 |  | $ 0 |  | $ 65,485 |
Senior Secured Notes, Unamortized Debt Discount |  |  |  |  |  | 1,828 |
Senior Notes, unamortized deferred financing costs |  |  |  |  |  | 175 |
Secured Long-term Debt, Noncurrent |  |  |  |  |  | 63,482 |
Repayment of 1.50% Senior Convertible Notes due 2021 | $ 65,500 |  |  |  |  |  |
Interest Expense, Debt |  | $ 0 | $ 1,100 | $ 2,300 | $ 6,600 |  |
Senior Secured Notes [Member] |  |  |  |  |  |  |
Senior Notes [Line Items] |  |  |  |  |  |  |
Senior Notes, Principal amount |  |  |  |  |  | 512,160 |
Senior Secured Notes, Unamortized Debt Discount |  |  |  |  |  | 39,771 |
Senior Notes, unamortized deferred financing costs |  |  |  |  |  | $ 11,733 |

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- Definition Amount, after accumulated amortization, of debt discount. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 1D -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611 + Details
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- Definition Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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