Organization (Details) $ in Thousands	3 Months Ended
Mar. 31, 2022 USD ($) candidate subsidiary	Dec. 31, 2021 USD ($)	Mar. 10, 2021 trial subject
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of additional trials \| trial			3
Number of clinical trial subjects \| subject			1,000
Number of product candidates \| candidate	4
Number of subsidiaries \| subsidiary	3
Accumulated deficit	$ 684,746	$ 674,547
Cash, cash equivalents and marketable securities	$ 79,038	$ 87,326

The cumulative amount of the reporting entity's undistributed earnings or deficit.

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