Summary of Significant Accounting Policies - Warranty Obligations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 30, 2017	Dec. 31, 2016	Dec. 26, 2015
Movement in Standard Product Warranty Accrual [Roll Forward]
Warranty Accrual beginning balance	$ 2,972	$ 1,116	$ 1,592
Warranty reserve from acquisition-Cascade Microtech	0	795	0
Accruals	8,115	5,254	2,536
Settlements	(7,425)	(4,193)	(3,012)
Warranty Accrual ending balance	$ 3,662	$ 2,972	$ 1,116

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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- Definition

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

+ References

+ Details

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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

+ Details

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- Definition

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

+ References

+ Details

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