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Fair value measurements - Schedule of Fair Value of Deferred Compensation Plan Assets (Details) - Deferred Compensation Plan Assets - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Opening balance	$ 68,356	$ 56,992	$ 61,549	$ 51,983
Additions (net of redemption)	834	747	3,179	1,547
Change in fair value of deferred compensation plan assets	4,089	3,252	8,551	7,461
Closing balance	$ 73,279	$ 60,991	$ 73,279	$ 60,991

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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