Shareholders' equity - Change in accumulated other comprehensive income, net of tax (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 29, 2024	Oct. 01, 2023
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 4,440,988	$ 4,021,968
Other comprehensive (loss) income before reclassifications	(20,977)	(4,335)
Amounts reclassified from accumulated other comprehensive (loss) income	77,142	(4,293)
Net current-period other comprehensive (loss) income	56,165	(8,628)
Ending balance	4,481,717	4,314,048
Palette Life Sciences AB
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Foreign currency translation adjustment	19,700
Cash Flow Hedges
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	1,396	4,931
Other comprehensive (loss) income before reclassifications	(6,249)	9,109
Amounts reclassified from accumulated other comprehensive (loss) income	(2,677)	(8,320)
Net current-period other comprehensive (loss) income	(8,926)	789
Ending balance	(7,530)	5,720
Pension and Other Postretirement Benefit Plans
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(88,049)	(135,799)
Other comprehensive (loss) income before reclassifications	8,280	(76)
Amounts reclassified from accumulated other comprehensive (loss) income	79,819	4,027
Net current-period other comprehensive (loss) income	88,099	3,951
Ending balance	50	(131,848)
Foreign Currency Translation Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(227,752)	(272,654)
Other comprehensive (loss) income before reclassifications	(23,008)	(13,368)
Amounts reclassified from accumulated other comprehensive (loss) income	0	0
Net current-period other comprehensive (loss) income	(23,008)	(13,368)
Ending balance	(250,760)	(286,022)
Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(314,405)	(403,522)
Ending balance	$ (258,240)	$ (412,150)

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Foreign Currency Translation

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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