Changes in accumulated other comprehensive income (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2023	Jul. 02, 2022	Jul. 01, 2023	Jul. 02, 2022
Accumulated Other Comprehensive Income [Roll Forward]
Beginning of Period			$ (278,472)	$ (359,084)
Other comprehensive income before reclassification			38,918	(63,106)
Amounts reclassified from accumulated other comprehensive income			(14,158)	7,817
Net current-period other comprehensive income			24,760	(55,289)
End of Period	$ (253,712)	$ (414,373)	(253,712)	(414,373)
Accumulated Other Comprehensive (income) Loss, Defined Benefit Plan, Tax	(1,900)	(35,400)	(1,900)	(35,400)
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Tax	16,100	9,300	16,100	9,300
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, Tax			100	4,100
Unrealized gain on interest rate swap, tax	2,172	2,923	(738)	13,815
Other Comprehensive Income (Loss), Unrealized Gain (loss) Certain Investments, Tax				(400)
Accumulated Translation Adjustment
Accumulated Other Comprehensive Income [Roll Forward]
Beginning of Period			(205,345)	(97,654)
Other comprehensive income before reclassification			31,851	(119,402)
Amounts reclassified from accumulated other comprehensive income			0	0
Net current-period other comprehensive income			31,851	(119,402)
End of Period	(173,494)	(217,056)	(173,494)	(217,056)
Accumulated Defined Benefit Plans Adjustment
Accumulated Other Comprehensive Income [Roll Forward]
Beginning of Period			(121,701)	(249,696)
Other comprehensive income before reclassification			6,106	(26,199)
Amounts reclassified from accumulated other comprehensive income			1,126	0
Net current-period other comprehensive income			(4,980)	26,199
End of Period	(126,681)	(223,497)	(126,681)	(223,497)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent | Interest Rate Swap
Accumulated Other Comprehensive Income [Roll Forward]
Beginning of Period			48,574	(13,064)
Other comprehensive income before reclassification			13,173	31,427
Amounts reclassified from accumulated other comprehensive income			(15,284)	7,817
Net current-period other comprehensive income			(2,111)	39,244
End of Period	46,463	26,180	46,463	26,180
AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-Sale, Parent
Accumulated Other Comprehensive Income [Roll Forward]
Beginning of Period			0	1,330
Other comprehensive income before reclassification			0	(1,330)
Amounts reclassified from accumulated other comprehensive income			0	0
Net current-period other comprehensive income			0	(1,330)
End of Period	$ 0	$ 0	$ 0	$ 0