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The increase in ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount under certain corporate activity .

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Long-Term Debt - Convertible Senior Notes Due 2026 (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($) $ / shares	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($) $ / shares shares	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Interest expense	$ 5,943,000	$ 7,179,000	$ 12,055,000	$ 14,573,000
Amortization of debt issuance costs			$ 1,587,000	$ 1,619,000
Convertible Senior Notes Maturing February 2026
Debt Instrument [Line Items]
Interest rate (as a percent)	6.75%		6.75%
Maturity date			Feb. 15, 2026
Frequency of periodic payment			semi-annually
Initial conversion ratio			0.1433795
Aggregate number of shares \| shares			28,675,900
Initial conversion price per share (USD per share) \| $ / shares	$ 6.97		$ 6.97
Increase in the conversion rate			0.0645207
Redemption price as a percentage of principal amount			100.00%
Unamortized debt discount and debt issuance costs					$ 47,300,000
Unamortized debt issuance costs	$ 6,500,000		$ 6,500,000
Effective interest rate (as a percent)	7.60%		7.60%		12.40%
Interest expense	$ 3,700,000		$ 7,300,000
Coupon interest expense	3,400,000		6,700,000
Amortization of debt issuance costs	$ 300,000		$ 600,000
Convertible Senior Notes Maturing February 2026 \| Minimum
Debt Instrument [Line Items]
Percentage of closing price of common stock to conversion price			130.00%
Number of trading days			5
Number of consecutive trading days			10
Convertible Senior Notes Maturing February 2026 \| Maximum
Debt Instrument [Line Items]
Percentage of closing price of common stock to conversion price			97.00%
Number of trading days			20
Number of consecutive trading days			30