Marketable Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Short-term marketable securities
Gross Amortized Cost	$ 291,029	$ 149,462
Total Unrealized Gains	3	79
Total Unrealized Losses	(214)	(20)
Fair Value	290,818	149,521
Long-term marketable securities
Gross Amortized Cost	168,233	120,029
Total Unrealized Gains	0	38
Total Unrealized Losses	(466)	(45)
Fair Value	167,767	120,022
Commercial paper
Short-term marketable securities
Gross Amortized Cost	116,937	48,685
Total Unrealized Gains	1	31
Total Unrealized Losses	(36)	(2)
Fair Value	116,902	48,714
Corporate bonds
Short-term marketable securities
Gross Amortized Cost	166,311	78,282
Total Unrealized Gains	2	45
Total Unrealized Losses	(170)	(18)
Fair Value	166,143	78,309
Long-term marketable securities
Gross Amortized Cost	164,071	91,694
Total Unrealized Gains	0	35
Total Unrealized Losses	(437)	(40)
Fair Value	163,634	91,689
U.S. Treasury bills
Short-term marketable securities
Gross Amortized Cost		19,995
Total Unrealized Gains		2
Total Unrealized Losses		0
Fair Value		19,997
Long-term marketable securities
Gross Amortized Cost		25,000
Total Unrealized Gains		1
Total Unrealized Losses		(5)
Fair Value		24,996
Municipal bonds
Short-term marketable securities
Gross Amortized Cost	7,781	2,500
Total Unrealized Gains	0	1
Total Unrealized Losses	(8)	0
Fair Value	7,773	2,501
Long-term marketable securities
Gross Amortized Cost	4,162	3,335
Total Unrealized Gains	0	2
Total Unrealized Losses	(29)	0
Fair Value	$ 4,133	$ 3,337