Stockholders' Equity - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018
Percentage of fair market value of Commons stock date of grant	100.00%
Share based payment award number of shares of common stock for each share	1.5
Total unrecognized compensation cost related to non-vested share-based compensation arrangements	$ 2,000
Cost is expected to be recognized over a weighted average period	2 years 18 days
Weighted-average grant date fair value of the options granted	$ 1.06	$ 1.65
Total intrinsic value of options exercised	$ 0	$ 0
Restricted stock units released, value withheld	$ (30)	$ (156)
Unvested restricted stock awarded	557,816	443,036
Restricted Stock Units (RSUs)
Grant of non-qualified stock option	$ 10		$ 40
The intrinsic value of the restricted stock units	$ 2.51
Number of shares, vested	128,624	222,371
Restricted stock units released, intrinsic value	$ 300
Restricted stock units released, Shares withheld	14,174
Restricted stock units released, value withheld	$ 30
Unvested restricted stock awarded	371,877	295,357
Weighted-average grant date fair value of restricted stock awarded	$ 1.90	$ 2.28
2008 Equity Incentive Plan
Grant of non-qualified stock option	3,850,000
Performance Award \| Restricted Stock Units (RSUs)
Unvested restricted stock awarded	0

Percentage of fair market value of common stock date of grant.

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- Definition

Share based compensation arrangement by share based payment award number of shares of common stock for each share.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Value, after value of shares used to satisfy grantee's tax withholding obligation for award under share-based payment arrangement, of restricted shares issued. Excludes cash used to satisfy grantee's tax withholding obligation.

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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).

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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).

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

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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

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Number of shares authorized for issuance under share-based payment arrangement.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Intrinsic value of vested award under share-based payment arrangement. Excludes share and unit options.

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Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

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