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Investments and Fair Value Measurements - Available-For-Sale Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 287,307	$ 548,333
Gross Unrealized Gain	23	0
Gross Unrealized Loss	(957)	(8,647)
Fair Value	286,373	539,686
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	73,444	291,685
Gross Unrealized Gain	8	0
Gross Unrealized Loss	(4)	(3,697)
Fair Value	73,448	287,988
Corporate notes and bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	112,487	217,187
Gross Unrealized Gain	9	0
Gross Unrealized Loss	(931)	(4,494)
Fair Value	111,565	212,693
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	25,946
Gross Unrealized Gain	0
Gross Unrealized Loss	(12)
Fair Value	25,934
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	89	24,617
Gross Unrealized Gain	0	0
Gross Unrealized Loss	0	(286)
Fair Value	89	24,331
Municipal securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		2,322
Gross Unrealized Gain		0
Gross Unrealized Loss		(101)
Fair Value		2,221
Foreign government and supranational securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost		12,522
Gross Unrealized Gain		0
Gross Unrealized Loss		(69)
Fair Value		$ 12,453
Agency bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	9,854
Gross Unrealized Gain	0
Gross Unrealized Loss	(3)
Fair Value	9,851
U.S. Treasury securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	52,824
Gross Unrealized Gain	6
Gross Unrealized Loss	0
Fair Value	52,830
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	12,663
Gross Unrealized Gain	0
Gross Unrealized Loss	(7)
Fair Value	$ 12,656

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