Investments (Details 2) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)		1 or les
Short-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 516,882	$ 482,739
Unrealized Losses	(3,307)	(415)
Unrealized Gains		3
Estimated Fair Value	513,575	482,327
Long-term Investments [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	12,035	101,012
Unrealized Losses	(110)	(348)
Estimated Fair Value	$ 11,925	$ 100,664
U.S. Treasury debt securities \| Current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 or less	1 or less
Amortized Cost	$ 120,196	$ 70,653
Unrealized Losses	(965)	(163)
Estimated Fair Value	$ 119,231	$ 70,490
U.S. Treasury debt securities \| Non-current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)		Greater than 1
Amortized Cost		$ 9,989
Unrealized Losses		(35)
Estimated Fair Value		9,954
Municipal securities \| Current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 or less
Amortized Cost	$ 19,939	18,017
Unrealized Losses	(278)	(6)
Unrealized Gains		1
Estimated Fair Value	$ 19,661	$ 18,012
Municipal securities \| Non-current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)		Greater than 1
Amortized Cost		$ 9,034
Unrealized Losses		(42)
Estimated Fair Value		$ 8,992
Corporate debt securities \| Current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 or less	1 or less
Amortized Cost	$ 178,376	$ 169,736
Unrealized Losses	(1,657)	(187)
Estimated Fair Value	$ 176,719	$ 169,549
Corporate debt securities \| Non-current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	Greater than 1	Greater than 1
Amortized Cost	$ 12,035	$ 81,989
Unrealized Losses	(110)	(271)
Estimated Fair Value	$ 11,925	$ 81,718
Commercial Paper \| Current Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Maturity (in years)	1 or less	1 or less
Amortized Cost	$ 198,371	$ 224,333
Unrealized Losses	(407)	(59)
Unrealized Gains		2
Estimated Fair Value	$ 197,964	$ 224,276

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