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Restructuring and Other - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Restructuring Cost and Reserve
Contingent consideration adjustment	$ 7,800	$ 800	$ (16,460)	$ (9,236)
Acquisition related costs	500	800	2,300	4,100
Wireless Test
Restructuring Cost and Reserve
Impairment charges fixed assets	300		300
Semiconductor Test
Restructuring Cost and Reserve
Severance benefit and charges	$ 500	$ 1,700		$ 7,900
Semiconductor Test, Industrial Automation and Corporate
Restructuring Cost and Reserve
Severance benefit and charges			$ 2,100