Pensions and other postretirement benefit plans - Schedule of Retirement Plans (Details) - Pension benefits - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Funded plans
Defined Benefit Plans and Other Postretirement Benefit Plans
Accumulated benefit obligation	$ 1,319,619	$ 1,456,629
Projected benefit obligation	1,320,326	1,457,351
Fair value of plan assets	1,493,688	1,617,694
Underfunded plans
Defined Benefit Plans and Other Postretirement Benefit Plans
Accumulated benefit obligation	2,210	45,780
Projected benefit obligation	2,210	45,780
Fair value of plan assets	$ 0	$ 42,008

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

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- Definition

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480482/715-20-55-17

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-3

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-3

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- Definition

Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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