Supplemental Balance Sheet and Income Statement Information - Investment income (loss) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Investment income (loss)
Interest and dividend income	$ 15,474	$ 1,527	$ 4,705
Gains (losses) on marketable securities	(482)	30	(3,267)
Investment income (loss)	$ 14,992	$ 1,557	$ 1,438

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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