Restructuring charges and impairment charges - Charges Recognized (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Apr. 01, 2018
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 14,365	$ 3,063
Asset impairment charges	3,030
Restructuring and impairment charges	17,395	3,063
Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	13,538	2,656
Asset impairment charges	0
Restructuring and impairment charges	13,538
Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	827	407
Asset impairment charges	3,030
Restructuring and impairment charges	3,857
2019 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	12,975
2019 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	12,975
2019 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	0
2018 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1,011
2018 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	437
2018 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	574
Other restructuring programs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	379	790
Other restructuring programs \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	126	585
Other restructuring programs \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 253	205
2016 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges		2,149
2016 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		1,955
2016 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		194
2014 Footprint realignment plan
Restructuring Cost and Reserve [Line Items]
Restructuring charges		124
2014 Footprint realignment plan \| Termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		116
2014 Footprint realignment plan \| Other Restructuring costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 8

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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