Summary of significant accounting policies - Fair Value Measurements (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024
Fair Value Disclosures [Abstract]
Marketable securities	$ 394,878		$ 364,645
Marketable security unrealized gain	10,162	$ 4,613	14,600
Fair value on a recurring basis \| Money market funds
Fair Value Disclosures [Abstract]
Assets at fair value	$ 362,400		$ 338,100

Fair value portion of asset recognized for present right to economic benefit.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 100
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Amount of investment in marketable security, classified as current.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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-Name Accounting Standards Codification
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Amount of unrealized gain (loss) on investment in marketable security.

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