Investments - Investment Income (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Schedule of Investments
Realized gains	$ 81,516	$ 17,361	$ 189,013	$ 25,689
Unrealized (losses) gains	(14,432)	(14,013)	183,348	140,495
Investment income	67,084	3,348	372,361	166,184
Income from equity method investments	$ 3,091	$ 3,778	9,237	$ 4,555
Equity Method Investments
Schedule of Investments
Income from equity method investments			$ 12,500

Amount of unrealized and realized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of realized gain (loss) from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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