Long-term Debt, Net - Finance Expense Related to the Convertible Notes (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Amortization of discount (premium)	$ 3,260	$ (2,176)	$ 1,022
the “Notes” \| Convertible Debt
Debt Instrument [Line Items]
Amortization of discount (premium)	3,604
Amortization of debt issuance costs	334
Total finance expense recognized	$ 3,938

Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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

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