Equity and Other Investments and Fair Value Measurements - Reconciliation of Equity and Long-Term Investments Balances (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Fair Value Disclosures [Abstract]
Equity and long-term investments			$ 341,664	$ 444,432	$ 444,432
Purchases of trading securities			49,674		63,201
Proceeds from trading securities			(5,097)
Net sales and purchases of investments managed by ISP Fund			(71,926)
Changes in fair value, net	$ 31,510	$ (16,936)	(22,509)	$ (60,827)	(59,161)
Reclassification of current portion			50,943		(107,532)
Other			1,045		724
Equity and long-term investments	$ 343,794		$ 343,794		$ 341,664

Gain loss on other investments.

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Reclassification of current portion.

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Net sales and purchases of investments.

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The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle).

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Amount of revenue and income classified as other.

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Cash paid to purchase debt and equity securities, classified as operating activities, during the period; includes trading securities and any other investments classified as operating.

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Cash received from sale of investments in debt and equity securities, classified as operating activities, during the period; includes trading securities and any other investments classified as operating.

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