Segment information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	$ 628,301	$ 648,319	$ 1,825,977	$ 1,914,410
Operating profit	132,092	117,621	327,988	300,322
Operating Segments
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating profit	157,842	140,693	432,892	393,095
Unallocated expenses
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating profit	(25,750)	(23,072)	(104,904)	(92,773)
Americas
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	375,040	374,493	1,045,532	1,092,321
Americas | Operating Segments
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating profit	121,760	81,405	310,267	229,513
EMEA
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	135,649	140,518	423,416	442,110
EMEA | Operating Segments
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating profit	17,702	21,820	53,044	69,670
Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	68,213	77,864	188,411	213,869
Asia | Operating Segments
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating profit	10,099	21,460	33,957	50,699
OEM
Revenues from External Customers and Long-Lived Assets [Line Items]
Net revenues	49,399	55,444	168,618	166,110
OEM | Operating Segments
Revenues from External Customers and Long-Lived Assets [Line Items]
Operating profit	$ 8,281	$ 16,008	$ 35,624	$ 43,213