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Summary of Significant Accounting Policies - Additional Information (Details) $ / shares in Units, $ in Thousands, shares in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($) $ / shares shares	Dec. 31, 2018 USD ($)
RECENT ACCOUNTING PRONOUNCEMENTS
Number of operating segments \| segment	1
Asset held for sale		$ 0	$ 7,000
In-process research and development	$ 0	7,000	$ 0
Common stock issued upon conversion \| shares			1.1
Gain (loss) on extinguishment of debt	426	0	$ 0
Change in fair value of derivative liabilities	$ 0	$ 0	(3,187)
Contractual term	10 years
Series B Warrants
RECENT ACCOUNTING PRONOUNCEMENTS
Change in fair value of derivative liabilities			1,900
Convertible notes \| The Convertible Notes
RECENT ACCOUNTING PRONOUNCEMENTS
Debt instrument, face amount			$ 8,800	$ 8,800
Price per share (in USD per share) \| $ / shares			$ 8.69
Gain (loss) on extinguishment of debt			$ (300)
Convertible notes \| The Convertible Notes \| Series B Warrants
RECENT ACCOUNTING PRONOUNCEMENTS
Change in fair value of derivative liabilities			3,200
Convertible notes \| The Convertible Notes \| Additional Paid in Capital
RECENT ACCOUNTING PRONOUNCEMENTS
Gain (loss) on extinguishment of debt			$ 13,000
Stock options
RECENT ACCOUNTING PRONOUNCEMENTS
Expected dividend yield	0.00%	0.00%	0.00%
Minimum
RECENT ACCOUNTING PRONOUNCEMENTS
Vesting period	1 year
Maximum
RECENT ACCOUNTING PRONOUNCEMENTS
Vesting period	3 years