Liquidity, Going Concern and Management Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023
Compensating Balances [Line Items]
Cash, cash equivalents, restricted cash, and restricted cash equivalents	$ 161,328		$ 161,328		$ 251,420
Working capital deficit	(165,300)		(165,300)
Accumulated deficit	(1,926,824)		(1,926,824)		$ (1,845,542)
Net loss from continuing operations	(25,833)	$ (54,209)	(82,162)	$ (137,577)
2026 Convertible notes | Convertible Debt
Compensating Balances [Line Items]
Debt instrument, repurchased face amount	$ 27,000		27,000
Sales agreement
Compensating Balances [Line Items]
Proceeds from issuance of common stock			36,900
Deduction of commission and expenses			$ 800
Issuance of common stock, net of offering costs (in shares)			28,791,969
Weighted average gross sale price per share	$ 1.31		$ 1.31