Stockholders' Equity and Stock-Based Compensation - Summary of Activity under Incentive Plan (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 30, 2019 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Additional General Disclosures [Abstract]
Outstanding, Number of Shares, Beginning Balance \| shares	844,898
Number of Shares, Options Granted \| shares	31,700
Number of Shares, Options Exercised \| shares	(208)
Number of Shares, Options Cancelled or forfeited \| shares	(54,140)
Outstanding, Number of Shares, Ending Balance \| shares	822,250
Outstanding, Weighted Average Exercise Price Per Share, Beginning Balance \| $ / shares	$ 8.84
Weighted Average Exercise Price Per Share, Options Granted \| $ / shares	4.33
Weighted Average Exercise Price Per Share, Options Exercised \| $ / shares	3.49
Weighted Average Exercise Price Per Share, Options Cancelled or forfeited \| $ / shares	10.16
Outstanding, Weighted Average Exercise Price Per Share, Ending Balance \| $ / shares	$ 8.58
Aggregate Intrinsic Value, Ending Balance \| $	$ 22

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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