Cash and Investments in Marketable Securities - Schedule of Cash and Investments in Marketable Securities, Including Cash Equivalents (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Estimated Fair Value at
Cash and cash equivalents	$ 25,218	$ 198,955
Short-term investments	708,737	862,941
Long-term investments	64,828	136,662
Total cash and investments in marketable securities	$ 798,783	$ 1,198,558