Schedule of Changes in Fair Value of Level 3 Contingent Consideration (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2016	Jul. 05, 2015	Jul. 03, 2016	Jul. 05, 2015
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payments of contingent consideration			$ 11,697
Increase in contingent consideration	$ 1,300		2,478	$ (1,600)
Universal Robots
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payments of contingent consideration			$ 15,000
EBITDA contingent consideration amount, percentage	100.00%		100.00%
Increase in contingent consideration	$ 800		$ 1,900
ZTEC Instruments, Inc.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Increase in contingent consideration		$ (1,600)		(1,600)
Avionics Interface Technologies, LLC
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Increase in contingent consideration	$ 600		$ 600
Contingent Consideration | ZTEC Instruments, Inc.
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Increase in contingent consideration		$ 0		$ 0