Financial Instruments (Details) $ in Thousands	9 Months Ended
Sep. 30, 2025 USD ($) item	Sep. 30, 2024 USD ($) item	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	$ 1,042,438		$ 968,606
Gross Unrealized Loss			(330)
Estimated Fair Value	1,042,438		968,276
Cash, cash equivalents and restricted cash	1,041,438	$ 892,844	945,587	$ 642,095
Short-term investments	$ 1,000		22,689
Number of investments sold \| item	0	1
Credit loss reserve	$ 0		0
Cash, cash equivalents, and restricted cash
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	1,041,438		945,587
Estimated Fair Value	1,041,438		945,587
Municipal securities
Debt Securities, Available-for-sale, Fair Value to Amortized Cost [Abstract]
Amortized Cost	1,000		23,019
Gross Unrealized Loss			(330)
Estimated Fair Value	$ 1,000		$ 22,689

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

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

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Cash, cash equivalents, restricted cash and amortized cost of investment in securities measured at fair value.

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Represents the number of investments sold.

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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.

+ References

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-Topic 320
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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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