Summary of Significant Accounting Policies - Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Accounting policies:
Eligible for reimbursement (as a percent of R&D expense)	43.50%	43.50%
Research and development incentive income and receivable
Balance at the beginning of the year	$ 185	$ 836
Australian research and development incentive income, net	231	132
Cash received for eligible expenses	(331)	(757)
Foreign currency translation	(12)	(26)
Balance at the end of the year	73	185
Other Assets
Deferred costs	345	831
Deposits	980	1,099
Uncertain tax positions	$ 0	0
Incremental borrowing rate	8.00%
Service agreements
Other Assets
Deposits	$ 980	$ 1,099
Computer equipment
Other Assets
Useful life (in years)	3 years
Lab equipment
Other Assets
Useful life (in years)	5 years
Computer office equipment
Other Assets
Useful life (in years)	5 years
Furnitures and fixtures
Other Assets
Useful life (in years)	5 years