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Employee benefit plans - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 01, 2018	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Deferred compensation plan liability		$ 72,663		$ 72,663		$ 60,924
Cash surrender value of policies		73,279		73,279		$ 61,549
Change in fair value of plan assets		4,089	$ 3,252	8,551	$ 7,461
Change in fair value of deferred compensation liabilities		$ 4,097	$ 3,297	$ 8,560	$ 7,453
U.S.
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Vesting percentage of participants (in percentage)	100.00%
Employer discretionary vesting period	2 years
Earnings receivable minimum term	2 years
Earnings receivable lump sum or annual installment maximum terms	15 years
Deferred compensation arrangement with individual, maximum re-deferral contractual term	10 years
U.S. | One-Year Anniversary of Approval of Contribution
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Employer discretionary vesting percentage (in percentage)	50.00%
U.S. | Two-Year Anniversary of Approval of Contribution
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Employer discretionary vesting percentage (in percentage)	50.00%
Minimum | U.S.
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Individual qualifying base compensation (in percentage)	1.00%
Individual qualifying bonus compensation (in percentage)	1.00%
Maximum | U.S.
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Individual qualifying base compensation (in percentage)	80.00%
Individual qualifying bonus compensation (in percentage)	100.00%

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Deferred Compensation Arrangement with Individual, Maximum Re-Deferral Contractual Term

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Deferred compensation arrangement with individual, participants’ deferrals vesting percentage.

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Deferred compensation arrangement with individual, qualifying bonus compensation percentage.

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Income (expense) on deferred compensation arrangement liability.

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Income (expense) on deferred compensation arrangement, plan assets.

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Carrying amount as of the balance sheet date of amounts which could be received based on the terms of the insurance contract upon surrendering life policies owned by the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(17))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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Commitment made to pay deferred cash remuneration expressed as a percentage of the individual's base salary.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Maximum term of the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Minimum period the individual is required to perform services to be fully vested under the deferred compensation arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements. Represents currently earned compensation under compensation arrangements that is not actually paid until a later date.

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