Marketable Securities - AFS Debt Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Marketable securities available for sale, consisting of debt securities:
Amortized Cost	$ 128,751	$ 148,539
Gross Unrealized Losses	(1,185)	(212)
Estimated Market Value	127,566	148,327
Commercial paper
Marketable securities available for sale, consisting of debt securities:
Amortized Cost	32,614	57,369
Estimated Market Value	32,614	57,369
Corporate debt securities
Marketable securities available for sale, consisting of debt securities:
Amortized Cost	37,209	39,825
Gross Unrealized Losses	(425)	(77)
Estimated Market Value	36,784	39,748
Asset backed Securities
Marketable securities available for sale, consisting of debt securities:
Amortized Cost	13,979	26,736
Gross Unrealized Losses	(130)	(29)
Estimated Market Value	13,849	26,707
Government and agency securities
Marketable securities available for sale, consisting of debt securities:
Amortized Cost	44,949	24,609
Gross Unrealized Losses	(630)	(106)
Estimated Market Value	$ 44,319	$ 24,503

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).

+ References

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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), classified as current.

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