Fair Value Measurements - Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Jul. 01, 2018
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Payment of contingent consideration	$ 0	$ (1,000)
Fair Value, Inputs, Level 3 \| Fair Value, Measurements, Recurring
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning balance	2,554
Ending balance	1,691
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	(1,019)
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	$ 156

Payment of contingent consideration from a business combination

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

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- Definition

Amount of addition (reduction) to the amount at which a liability could be incurred (settled) in a current transaction between willing parties.

+ References

No definition available.

+ Details

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