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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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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.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Senior Secured Notes (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
Senior Secured Notes (Details) - USD ($) $ in Thousands	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