Selected Quarterly Consolidated Financial Data (Unaudited) (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Dec. 31, 2016	Oct. 01, 2016	Jul. 02, 2016	Apr. 02, 2016	Jan. 02, 2016	Oct. 03, 2015	Jul. 04, 2015	Apr. 04, 2015	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Quarterly Results Of Operations [Line Items]
Net sales	$ 28,982	$ 22,559	$ 14,918	$ 13,664	$ 16,398	$ 18,418	$ 20,458	$ 19,885	$ 80,124	$ 75,160	$ 65,550
Gross profit	11,912	8,515	6,127	3,856	6,677	4,912	7,806	6,922	30,409	26,317	17,433
Net income (loss)	$ 2,835	$ (481)	$ (3,490)	$ (6,305)	$ (2,526)	$ (3,759)	$ 12	$ (2,893)	$ (7,441)	$ (9,166)	$ (27,445)
Basic net income (loss) per share	$ 0.14	$ (0.02)	$ (0.17)	$ (0.31)
Diluted net income (loss) per share	$ 0.13	$ (0.02)	$ (0.17)	$ (0.31)
Basic and diluted net income (loss) per share					$ (0.12)	$ (0.17)		$ (0.12)	$ (0.36)	$ (0.41)	$ (1.16)

Quarterly Results Of Operations [Line Items]

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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