Supplemental Balance Sheet and Income Statement Information - Investment income (loss) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Investment income (loss)
Interest and dividend income	$ 10,041	$ 4,814	$ 30,573	$ 6,535
Gains (losses) on marketable securities	128	(1)	1,205	(737)
Investment income (loss)	$ 10,169	$ 4,813	$ 31,778	$ 5,798

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

Reference 1: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(c),9(a))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a),(b))
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-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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No definition available.

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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