Stockholders' Equity - Restricted Stock Units and Awards (Details) - $ / shares	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019
Restricted stock units and awards
Number of Shares, Restricted stock granted	557,816	443,036
Restricted Stock Units (RSUs)
Restricted stock units and awards
Outstanding, Number of Shares, Beginning Balance	411,133	597,121
Number of Shares, Restricted stock granted	371,877	295,357
Number of Shares, Restricted stock released	(128,624)	(222,371)
Number of Shares, Restricted stock forfeited	(129,535)	(258,974)
Outstanding, Number of Shares, Ending Balance	524,851	411,133
Outstanding, Weighted Average Grant Date Fair Value, Beginning Balance	$ 7.19	$ 9.08
Weighted Average Grant Date Fair Value, Restricted stock granted	1.90	2.28
Weighted Average Grant Date Fair Value, Restricted stock released	2.14	4.32
Weighted Average Grant Date Fair Value, Restricted stock forfeited	5.48	8.41
Outstanding, Weighted Average Grant Date Fair Value, Ending Balance	$ 5.10	$ 7.19

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)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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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
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(3)
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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
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
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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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-Publisher FASB
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-Paragraph 2
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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
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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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.

+ References

No definition available.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
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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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- Definition

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.

+ References

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