Fair value of financial instruments and marketable securities - Marketable Securities, Unrealized Gains (Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Fair value of financial instruments and marketable securities
Amortized Cost	$ 1,148,927		$ 1,148,927		$ 928,340
Gross Unrealized, Gains	8		8		805
Gross Unrealized, Losses	(1,371)		(1,371)		(18)
Fair Value	1,147,564		1,147,564		929,127
Write downs of available for sale debt securities	0	$ 0	0	$ 0
Increase in allowance for credit losses	0	$ 0	0	$ 0
Commercial paper
Fair value of financial instruments and marketable securities
Amortized Cost	134,989		134,989		93,113
Gross Unrealized, Gains	1		1		8
Gross Unrealized, Losses	(82)		(82)		(9)
Fair Value	134,908		134,908		93,112
Corporate debt securities
Fair value of financial instruments and marketable securities
Amortized Cost	510,870		510,870		279,090
Gross Unrealized, Gains	2		2		181
Gross Unrealized, Losses	(797)		(797)		(9)
Fair Value	510,075		510,075		279,262
Government obligations
Fair value of financial instruments and marketable securities
Amortized Cost	503,068		503,068		556,137
Gross Unrealized, Gains	5		5		616
Gross Unrealized, Losses	(492)		(492)
Fair Value	$ 502,581		$ 502,581		$ 556,753

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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