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Restructuring and impairment charges (credits) - Charges Recognized (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jul. 01, 2018	Jun. 30, 2019	Jul. 01, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	$ (2,196)	$ 53,488	$ 12,169	$ 56,551
Asset impairment charges	3,881	1,865	6,911	1,865
Restructuring and impairment charges	1,685	55,353	19,080	58,416
Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	(2,672)	52,919	10,866	55,576
Asset impairment charges	0	0	0	0
Restructuring and impairment charges	(2,672)	52,919	10,866	55,576
Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	476	569	1,303	975
Asset impairment charges	3,881	1,865	6,911	1,865
Restructuring and impairment charges	4,357	2,434	8,214	2,840
2019 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	(429)		12,546
2019 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	(459)		12,516
2019 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	30		30
2018 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	(2,141)	52,474	(1,130)	52,474
2018 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	(2,275)	52,345	(1,838)	52,345
2018 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	134	129	708	129
Other restructuring programs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	374	1,014	753	1,587
Other restructuring programs \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	62	574	188	1,032
Other restructuring programs \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)	$ 312	$ 440	$ 565	555
2016 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)				2,490
2016 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)				2,199
2016 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges (credits)				$ 291