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Fair Value of Financial Assets and Liabilities - Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Fair Value of Financial Assets
Amortized Cost	$ 234,842	$ 205,702
Gross Unrealized Gains	11
Gross Unrealized Losses	(185)	(91)
Fair Value	234,668	205,611
Corporate debt securities and commercial paper
Fair Value of Financial Assets
Amortized Cost	234,842	205,702
Gross Unrealized Gains	11
Gross Unrealized Losses	(185)	(91)
Fair Value	$ 234,668	$ 205,611

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- Definition

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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