Cash, Cash Equivalents and Short-Term Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Cash and Cash Equivalents
Cash	$ 34,752	$ 27,788
Cash equivalents:
Money market mutual fund	1,843	111,313
Total cash and cash equivalents	36,595	139,101
Short-term investments:
Total short-term investments	486,728	489,698
Cash, cash equivalents and short-term investments	523,323	628,799
U.S. Treasury notes and bills
Short-term investments:
Short-term Investments	190,718	223,896
Mutual funds
Short-term investments:
Short-term Investments	99,777	110,006
Corporate debt securities
Short-term investments:
Short-term Investments	$ 196,233	$ 155,796

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