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Cash, cash equivalents, restricted cash and amount of unrealized loss in securities measured at fair value.

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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), with single maturity date and allocated without single maturity date, maturing in second through fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Fair value of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), with single maturity date and allocated without single maturity date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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Amount of allowance for credit loss 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 of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Financial Instruments (Details) $ in Thousands	9 Months Ended
Financial Instruments (Details) $ in Thousands	Sep. 30, 2024 USD ($) security position	Dec. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	$ 922,878	$ 881,708
Gross Unrealized Gain		14
Gross Unrealized Loss	(544)	(2,745)
Estimated Fair Value	922,334	878,977
Cash, cash equivalents and restricted cash	892,844	642,095	$ 668,710	$ 466,091
Short-term investments	$ 29,490	236,882
Number of investments sold \| security	1
Number of investments, unrealized loss position \| position	9
Credit loss reserve	$ 0
Fair value	27,990
Unrealized loss	(544)
Amortized Cost
Less than or equal to one year	29,034
Greater than one year but less than five years	1,000
Total	30,034
Fair Value
Less than or equal to one year	28,522
Greater than one year but less than five years	968
Total	29,490
Cash, cash equivalents, and restricted cash
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	892,844	642,095
Estimated Fair Value	892,844	642,095
U.S. Treasury securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost		201,522
Gross Unrealized Gain		14
Gross Unrealized Loss		(1,118)
Estimated Fair Value		200,418
Municipal securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	30,034	38,091
Gross Unrealized Loss	(544)	(1,627)
Estimated Fair Value	29,490	$ 36,464
Fair value	27,990
Unrealized loss	$ (544)