Other Current Assets and Other Long-Term Assets - Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other long-term assets	$ 17,709	$ 9,157
Deposits paid for research and development	17,100	8,600
Security deposit for lease	$ 600	$ 600