Accumulated other comprehensive income (loss) (Details) $ in Thousands	9 Months Ended
	Sep. 26, 2020 USD ($)
Accumulated Other Comprehensive Income Rollforward [Roll Forward]
Beginning balance	$ 8,126,448
Current period other comprehensive income (loss)	(169,599)
Ending balance	8,167,069
Foreign currency translation adjustments
Accumulated Other Comprehensive Income Rollforward [Roll Forward]
Beginning balance	(753,108)
Current period other comprehensive income (loss)	(169,763)
Ending balance	(922,871)
Pensions, net of tax
Accumulated Other Comprehensive Income Rollforward [Roll Forward]
Beginning balance	(12,716)
Current period other comprehensive income (loss)	164
Ending balance	(12,552)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income Rollforward [Roll Forward]
Beginning balance	(765,824)
Ending balance	$ (935,423)