Revenue Recognition - Summary of Consideration Allocated to Performance Obligations (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Deferred revenue, current	$ 1,989	$ 1,705
Deferred revenue, net of current portion	862	802
Unsatisfied Training Obligations
Disaggregation of Revenue [Line Items]
Deferred revenue, current	156	67
Unsatisfied Contract-term Services
Disaggregation of Revenue [Line Items]
Deferred revenue, current	1,015	849
Deferred revenue, net of current portion	569	544
Total Deferred Revenue	1,584	1,393
Unsatisfied Pellet Procedures
Disaggregation of Revenue [Line Items]
Deferred revenue, current	818	789
Deferred revenue, net of current portion	293	258
Total Deferred Revenue	$ 1,111	$ 1,047