Balance Sheet Classification of Warranty Provision Account (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Jul. 01, 2017	Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Jan. 02, 2016
Product Warranty [Line Items]
Other accrued liabilities	$ 915		$ 829
Other long-term liabilities	220		178
Total warranty provision	$ 1,135	$ 1,220	$ 1,007	$ 722	$ 592	$ 982

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.

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability.

+ 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),(c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

+ Details

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid within one year or the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

+ References

No definition available.

+ Details

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- Definition

Amount as of the balance sheet date of the aggregate standard product warranty liability that is expected to be paid after one year or beyond the normal operating cycle, if longer. Does not include the balance for the extended product warranty liability.

+ References

No definition available.

+ Details

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