Note 8 - Stock-Based Compensation - Stock Options Activity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended	12 Months Ended
Jul. 04, 2021	Jan. 03, 2021
Balance, options (in shares)	121
Weighted average price balance (in dollars per share)	$ 28.46
Weighted average remaining term, balance (Year)	3 years 1 month 28 days	3 years 9 months
Forfeited or expired (in shares)	(11)
Weighted average price, forfeited or expired (in dollars per share)	$ 19.59
Balance, options (in shares)	110	121
Weighted average price balance (in dollars per share)	$ 29.31	$ 28.46
Aggregate intrinsic value	$ 0
Exercisable (in shares)	110
Weighted average price, exercisable (in dollars per share)	$ 29.31
Weighted average remaining term, exercisable (Year)	3 years 1 month 28 days
Aggregate intrinsic value, exercisable	$ 0
Vested and expected to vest (in shares)	110
Weighted average price, vested and expected to vest (in dollars per share)	$ 29.31
Weighted average remaining term, vested and expected to vest (Year)	3 years 1 month 28 days
Aggregate intrinsic value, vested and expected to vest	$ 0

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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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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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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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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