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Restructuring and impairment charges (credits) - Charges Recognized (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 28, 2020	Jun. 30, 2019	Jun. 28, 2020	Jun. 30, 2019
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	$ 19,005	$ (2,196)	$ 20,351	$ 12,169
Asset impairment charges		3,881		6,911
Restructuring and impairment charges	19,005	1,685	20,351	19,080
Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	18,601	(2,672)	19,637	10,866
Asset impairment charges		0		0
Restructuring and impairment charges		(2,672)		10,866
Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	404	476	714	1,303
Asset impairment charges		3,881		6,911
Restructuring and impairment charges		4,357		8,214
2020 Workforce reduction plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	10,564		10,564
2020 Workforce reduction plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	10,564		10,564
2020 Workforce reduction plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	0		0
2019 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	405	(429)	1,243	12,546
2019 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	323	(459)	1,152	12,516
2019 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	82	30	91	30
2018 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	7,597	(2,141)	7,992	(1,130)
2018 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	7,545	(2,275)	7,859	(1,838)
2018 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	52	134	133	708
Other restructuring programs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	439	374	552	753
Other restructuring programs \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	169	62	62	188
Other restructuring programs \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	$ 270	$ 312	$ 490	$ 565