Convertible Senior Notes (Details) $ / shares in Units, $ in Thousands				3 Months Ended		9 Months Ended
	Jul. 16, 2021 USD ($) shares	Nov. 06, 2020 USD ($) D	Oct. 17, 2018 USD ($) D $ / shares	Sep. 30, 2022 USD ($) $ / shares	Dec. 31, 2019 USD ($)	Sep. 30, 2022 USD ($) $ / shares	Dec. 31, 2021 $ / shares	Jul. 01, 2021 USD ($)	Mar. 31, 2020 USD ($)
Convertible Notes
Common stock, par value (in dollars per share) | $ / shares				$ 0.0001		$ 0.0001	$ 0.0001
Other Nonoperating Income (Expenses)				$ 20		$ 54
Notes outstanding				24,399		24,399
Debt, carrying value				$ 25,000		$ 25,000
2018 Notes
Convertible Notes
Aggregate principal amount			$ 150,000
Interest rate (as a percent)			5.00%	5.00%		5.00%
Net proceeds			$ 145,300
Common stock, par value (in dollars per share) | $ / shares			$ 0.0001
Initial conversion rate			139.5771
Initial conversion price of Common Stock | $ / shares			$ 7.16
Percentage of stock price trigger for conversion			130.00%
Trading days | D			20
Consecutive trading days | D			30
2019 Notes
Convertible Notes
Debt Conversion, Original Debt, Amount					$ 121,700
Debt Conversion, Converted Instrument, Amount					66,900
Repayments of Convertible Debt					$ 12,100
Interest rate (as a percent)					5.00%
Debt, carrying value									$ 0
2020 Notes
Convertible Notes
Aggregate principal amount		$ 28,000						$ 28,000
Debt Conversion, Converted Instrument, Amount	$ 28,000	$ 28,000
Interest rate (as a percent)		5.00%
Percentage of stock price trigger for conversion		123.08%
Trading days | D		20
Consecutive trading days | D		30
Debt Conversion, Converted Instrument, Shares Issued | shares	8,615,384