Investments - Narrative (Details) - USD ($)	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021
Investments
Investments, realized gains or losses	$ 0	$ 0
Marketable securities, gross unrealized loss position	92,700,000
Marketable securities, continuous unrealized loss position, greater than 12 months	0
Marketable securities, continuous unrealized loss position, less than 12 months	$ 52,600,000

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

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Amount of realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position without allowance for credit loss.

+ References

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