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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Financings - Convertible Senior Unsecured Notes (Details) - USD ($)		1 Months Ended	12 Months Ended
	Jul. 01, 2020	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2021	Mar. 31, 2021
Debt Instrument [Line Items]
Common stock, par value (in dollars per share)			$ 0.01	$ 0.01
Proceeds from convertible note offering			$ 86,250,000	$ 0	$ 90,625,000
2024 Notes
Debt Instrument [Line Items]
Debt instrument, repurchase amount		$ 20,300,000
Six Point Seventy Five Percent Convertible Senior Unsecured Notes Due 2022
Debt Instrument [Line Items]
Debt instrument, repurchase amount		100,300,000	$ 8,000,000.0	$ 25,000,000		$ 22,300,000	$ 6,700,000
Debt instrument, interest rate, effective percentage			1.00%	13.00%		2.80%	6.30%
Convertible Debt \| 2024 Notes
Debt Instrument [Line Items]
Interest rate, stated percentage			6.75%
Principal balance		86,300,000
Proceeds from convertible note offering		$ 83,300,000
Convertible Debt \| Six Point Seventy Five Percent Convertible Senior Unsecured Notes Due 2022
Debt Instrument [Line Items]
Interest rate, stated percentage			6.75%
Principal balance	$ 5,000,000		$ 37,700,000	$ 175,000,000
Redemption price, percentage			100.00%
Convertible senior unsecured notes, conversion price (in dollars per share)			$ 12.02
Redemption period			3 months
Exchange of convertible senior notes (in shares)	1,354,084
Common stock, par value (in dollars per share)	$ 0.01