Financial Instruments - Summery of Remaining Contractual Maturities of Company's Short-term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Adjusted Cost	$ 263,729	$ 53,568
Market Value	263,697	$ 53,567
Short Term Investments
Schedule Of Available For Sale Securities [Line Items]
Adjusted Cost	226,044
Market Value	226,012
Short Term Investments | Mature in 1 Year or Less
Schedule Of Available For Sale Securities [Line Items]
Adjusted Cost	220,980
Market Value	220,946
Short Term Investments | Mature in 1 to 2 Years
Schedule Of Available For Sale Securities [Line Items]
Adjusted Cost	5,064
Market Value	$ 5,066