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Investments - Non-equity method (Details) $ in Thousands		9 Months Ended		12 Months Ended
	Sep. 08, 2023 USD ($)	Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2025	Dec. 31, 2024 USD ($)	Aug. 22, 2023 USD ($)
Equity Securities without Readily Determinable Fair Value [Line Items]
Equity securities		$ 67,541				$ 92,541
Funded Commitment amount		$ 2,959	$ 0
Infinitum
Equity Securities without Readily Determinable Fair Value [Line Items]
Contributions	$ 24,600			$ 42,000
Ascend
Equity Securities without Readily Determinable Fair Value [Line Items]
Equity securities							$ 25,000
Conversion ratio		1
Commitment to purchase convertible debt		$ 3,000
Funded Commitment amount		$ 2,900
Redemption term		2 years
Funded commitments, Annual interest rate		15.00%
Funded commitments, redemption, multiplier		12
Ascend | Participating stockholders in convertible note purchase | Ascend
Equity Securities without Readily Determinable Fair Value [Line Items]
Conversion ratio					1
Ascend | Non-participating stockholders in convertible note purchase | Ascend
Equity Securities without Readily Determinable Fair Value [Line Items]
Conversion ratio					3

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Amount of cash outflow to acquire 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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Number of common shares issuable upon conversion for each share of preferred stock to be converted.

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