Fair Value Measurements - Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Oct. 01, 2017
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payment of contingent consideration	$ (1,000)	$ (1,926)
Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	3,557
Ending balance	2,507
Manatee | Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities, Fair Value Adjustment	(1,350)
GVi | Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities, Fair Value Adjustment	1,130
Payment of contingent consideration	(1,000)
Chiaro Technologies LLC [Member] | Fair Value, Inputs, Level 3 | Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Liabilities, Fair Value Adjustment	$ 170