Warranty - Summary of Current Period Charges, Adjustments to Previous Estimates, Settlements representing Actual Costs Incurred with regard to Accrued Warranty (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Guarantees and Product Warranties [Abstract]
Accrued Warranty, Beginning of Period	$ 5,323	$ 5,614	$ 5,386	$ 5,569
Accrued Warranty, Charged to Expense	2,851	3,045	5,217	6,088
Accrued Warranty, Adjustments	(98)	(153)	(208)	(64)
Accrued Warranty, Settlements	(2,708)	(2,827)	(5,027)	(5,914)
Accrued Warranty, End of Period	$ 5,368	$ 5,679	$ 5,368	$ 5,679

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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://fasb.org/us-gaap/role/ref/legacyRef
-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

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-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

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-Section 50
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-Subparagraph (c)(5)
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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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
-Subparagraph ((c)(2))
-URI http://asc.fasb.org/extlink&oid=68068213&loc=d3e12565-110249

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- Definition

Amount of increase (decrease) in the standard and extended product warranty accrual from changes in estimates attributable to preexisting product warranties.

+ 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
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