Investments - Schedule of Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Available-for-sale securities:
Short-term investments, Amortized Cost	$ 509,092	$ 315,767
Gross Unrealized Gains	3,709	1,461
Gross Unrealized Losses less than one year	(224)	(78)
Gross Unrealized Losses greater than one year	(31)	(1,759)
Short-term investments, Estimated Fair Value	512,571	316,022
Long-term investments, Amortized Cost	18,800	38,698
Total long-term investments	18,920	39,887
Long-term investments, Estimated Fair Value	18,775	38,067
Amortized Cost	528,037	356,285
Estimated Fair Value	531,491	355,909
Short-term investments
Available-for-sale securities:
Gross Unrealized Gains	3,709	1,461
Gross Unrealized Losses less than one year	(224)	(51)
Gross Unrealized Losses greater than one year	(6)	(1,155)
Long-term investments
Available-for-sale securities:
Gross Unrealized Losses less than one year	0	(27)
Gross Unrealized Losses greater than one year	(25)	(604)
Total long-term investments	18,920	39,887
Amortized Cost	18,945	40,518
Certificates of deposit
Available-for-sale securities:
Amortized Cost	145	1,820
Estimated Fair Value	145	1,820
Corporate debt securities
Available-for-sale securities:
Short-term investments, Amortized Cost	204,502	112,055
Short-term investments, Estimated Fair Value	206,292	112,207
Long-term investments, Amortized Cost	6,227	19,306
Long-term investments, Estimated Fair Value	6,215	19,017
Corporate debt securities \| Short-term investments
Available-for-sale securities:
Gross Unrealized Gains	1,892	703
Gross Unrealized Losses less than one year	(102)	(15)
Gross Unrealized Losses greater than one year		(536)
Corporate debt securities \| Long-term investments
Available-for-sale securities:
Gross Unrealized Losses less than one year	0
Gross Unrealized Losses greater than one year	(12)	(289)
U.S. government and agency debt securities
Available-for-sale securities:
Short-term investments, Amortized Cost	304,590	199,708
Short-term investments, Estimated Fair Value	306,279	199,819
Long-term investments, Amortized Cost	12,573	19,392
Long-term investments, Estimated Fair Value	12,560	19,050
U.S. government and agency debt securities \| Short-term investments
Available-for-sale securities:
Gross Unrealized Gains	1,817	758
Gross Unrealized Losses less than one year	(122)	(36)
Gross Unrealized Losses greater than one year	(6)	(611)
U.S. government and agency debt securities \| Long-term investments
Available-for-sale securities:
Gross Unrealized Losses less than one year	0	(27)
Gross Unrealized Losses greater than one year	$ (13)	(315)
Non-U.S. government debt securities
Available-for-sale securities:
Short-term investments, Amortized Cost		4,004
Short-term investments, Estimated Fair Value		3,996
Non-U.S. government debt securities \| Short-term investments
Available-for-sale securities:
Gross Unrealized Losses greater than one year		$ (8)

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