Investments - Available-for-sale securities (Details) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2024
Investments
Fair Value	$ 0	$ 0
Proceeds from sales and maturities of available-for-sale securities	1,400,000,000
Proceeds from sales of equity securities	$ 144,250,000

Amount of 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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+ Details