Fair Value Measurements - Recurring and Non-Recurring (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Fair Value Measurements
Short-term investments	$ 131,902	$ 53,774
Convertible notes	0	519,749
Senior notes	198,802	0
Level 1 \| Carrying Amount
Fair Value Measurements
Short-term investments	131,902	53,774
Level 1 \| Fair Value
Fair Value Measurements
Short-term investments	132,172	53,791
Level 3 \| Carrying Amount
Fair Value Measurements
Loans held for investment	638,167	113,144
Convertible notes	0	519,749
Senior notes	198,802	0
Level 3 \| Fair Value
Fair Value Measurements
Loans held for investment	644,593	113,348
Convertible notes	0	371,160
Senior notes	$ 132,013	$ 0

Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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