Shareholders' equity - Change in accumulated other comprehensive income, net of tax (Details) - USD ($) $ in Thousands	9 Months Ended
	Oct. 01, 2023	Sep. 25, 2022
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	$ 4,021,968	$ 3,754,748
Other comprehensive income (loss) before reclassifications	(4,335)	(114,725)
Amounts reclassified from accumulated other comprehensive (loss) income	(4,293)	2,492
Net current-period other comprehensive income (loss)	(8,628)	(112,233)
Ending balance	4,314,048	3,895,161
Cash Flow Hedges
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	4,931	1,081
Other comprehensive income (loss) before reclassifications	9,109	6,871
Amounts reclassified from accumulated other comprehensive (loss) income	(8,320)	(1,335)
Net current-period other comprehensive income (loss)	789	5,536
Ending balance	5,720	6,617
Pension and Other Postretirement Benefit Plans
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(135,799)	(138,290)
Other comprehensive income (loss) before reclassifications	(76)	1,980
Amounts reclassified from accumulated other comprehensive (loss) income	4,027	3,827
Net current-period other comprehensive income (loss)	3,951	5,807
Ending balance	(131,848)	(132,483)
Foreign Currency Translation Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(272,654)	(209,750)
Other comprehensive income (loss) before reclassifications	(13,368)	(123,576)
Amounts reclassified from accumulated other comprehensive (loss) income	0	0
Net current-period other comprehensive income (loss)	(13,368)	(123,576)
Ending balance	(286,022)	(333,326)
Accumulated Other Comprehensive (Loss) Income
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning balance	(403,522)	(346,959)
Ending balance	$ (412,150)	$ (459,192)