Stockholders' Equity - Restricted Stock Units and Awards (Details) - $ / shares	12 Months Ended
Dec. 29, 2018	Dec. 30, 2017
Restricted stock units and awards
Number of Shares, Restricted stock granted	628,125	212,538
Restricted Stock Units (RSUs)
Restricted stock units and awards
Outstanding, Number of Shares, Beginning Balance	361,148	335,805
Number of Shares, Restricted stock granted	418,750	137,391
Number of Shares, Restricted stock released	(86,941)	(80,009)
Number of Shares, Restricted stock forfeited	(95,836)	(32,039)
Outstanding, Number of Shares, Ending Balance	597,121	361,148
Outstanding, Weighted Average Grant Date Fair Value, Beginning Balance	$ 10.42	$ 11.20
Weighted Average Grant Date Fair Value, Restricted stock granted	7.79	9.88
Weighted Average Grant Date Fair Value, Restricted stock released	7.38	12.37
Weighted Average Grant Date Fair Value, Restricted stock forfeited	10.01	11.44
Outstanding, Weighted Average Grant Date Fair Value, Ending Balance	$ 9.08	$ 10.42
Restricted Stock Awards
Restricted stock units and awards
Outstanding, Number of Shares, Beginning Balance	4,301	1,289
Number of Shares, Restricted stock granted		4,301
Number of Shares, Restricted stock released	(4,301)	(1,289)
Outstanding, Number of Shares, Ending Balance		4,301
Outstanding, Weighted Average Grant Date Fair Value, Beginning Balance	$ 9.30	$ 15.51
Weighted Average Grant Date Fair Value, Restricted stock granted		9.30
Weighted Average Grant Date Fair Value, Restricted stock released	$ 9.30	15.51
Outstanding, Weighted Average Grant Date Fair Value, Ending Balance		$ 9.30

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

+ References

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-Publisher FASB
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-Topic 718
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-Paragraph 2
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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-Publisher FASB
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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