Supplemental Balance Sheet and Income Statement Information - Investment income (loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Investment income (loss)
Interest and dividend income	$ 4,814	$ 211	$ 6,535	$ 1,214
Gains (losses) on marketable securities	(1)	(11)	(737)	187
Investment income (loss)	$ 4,813	$ 200	$ 5,798	$ 1,401

Amount of realized and unrealized gain (loss) on investment.

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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations.

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