Prepaid Expenses - Schedule of Prepaid Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Prepaid clinical expenses	$ 3,459	$ 5,151
Prepaid software related expenses	4,294	479
Prepaid insurance expense	443	206
Other	937	740
Prepaid expenses	$ 9,133	$ 6,576

Amount of asset related to consideration paid in advance for insurance that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

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Name:	us-gaap_PrepaidInsurance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant