Accrued Warranty (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 28, 2018	Sep. 29, 2017
Product Warranties Disclosures [Abstract]
Balance at beginning of the period	$ 4,835	$ 3,142
Provision charged to cost of revenue	2,503	2,084
Warranty liabilities acquired from acquisitions		1,307
Use of provision	(2,243)	(1,818)
Foreign currency exchange rate changes	(54)	58
Balance at end of period	$ 5,041	$ 4,773

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- Definition

Amount of increase in the standard and extended product warranty accrual from a business acquisition.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 7
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
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-Subparagraph (SX 210.5-02.20)
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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

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- Definition

Amount of foreign currency translation gain (loss) which decreases (increases) the standard and extended product warranty accrual.

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