Commitments and Contingencies - Information Related to Operating Lease (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Commitments And Contingencies Disclosure [Abstract]
Operating lease expense (including variable costs of $95 and $83 during the three months ended September 30, 2021 and 2020, respectively, and $279, and $224 during the nine months ended September 30, 2021 and 2020, respectively)	$ 293	$ 277	$ 872	$ 813
Cash paid for amounts included in the measurement of lease liabilities	$ 215	$ 193	$ 640	$ 557