Summary of Significant Accounting Policies - Changes in Product Warranty Accrual (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017	Dec. 31, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Warranty accrual, beginning of period	$ 1,149	$ 910	$ 1,222
Accrual for warranties issued (including specific accrual)	1,549	1,061	871
Changes in pre-existing warranties (including changes in estimates)	(551)	(332)	(110)
Settlements made	(1,339)	(1,154)	(1,293)
Warranty accrual, end of period	$ 1,910	$ 1,149	$ 910

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

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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
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- Definition

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

+ References

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- Definition

The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.

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