Investments and Fair Value Measurements - Available-For-Sale Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 716,844	$ 892,948
Gross Unrealized Gain	0	1
Gross Unrealized Loss	(11,988)	(2,243)
Fair Value	704,856	890,706
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	333,938	425,560
Gross Unrealized Gain	0	1
Gross Unrealized Loss	(5,934)	(1,086)
Fair Value	328,004	424,475
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	255,927	209,550
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(5,177)	(925)
Fair Value	250,750	208,625
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,489	124,098
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	(9)
Fair Value	16,489	124,089
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	88,020	98,857
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(532)	(140)
Fair Value	87,488	98,717
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,325	4,577
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(86)	(15)
Fair Value	2,239	4,562
Foreign government and supranational securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	20,145	30,306
Gross Unrealized Gain	0	0
Gross Unrealized Loss	(259)	(68)
Fair Value	$ 19,886	$ 30,238

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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