v3.21.2

STOCK-BASED COMPENSATION (Tables) | 9 Months Ended
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Oct. 03, 2021
Stock-based Compensation |
Schedule of recognized stock-based compensation expense | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended | ​ | Nine Months Ended | ​
(in thousands) | ​ | October 3, 2021 | ​ | September 27, 2020 |  | October 3, 2021 |  | September 27, 2020 | ​
Stock options | ​ | $ | 62 | ​ | $ | 110 | ​ | $ | 245 | ​ | $ | 235 | ​
Restricted stock | ​ |  | 232 | ​ |  | 64 | ​ |  | 687 | ​ |  | 187 | ​
​ | ​ | $ | 294 | ​ | $ | 174 | ​ | $ | 932 | ​ | $ | 422 | ​
Schedule of stock option activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | ​ | ​ | ​ | Weighted
​ | ​ | ​ | ​ | ​ | ​ | ​ | Average
​ | ​ | ​ | ​ | ​ | ​ | ​ | Remaining
​ | ​ | Number of | ​ | Weighted Average | ​ | Contractual
(number of options in thousands) |  | Options |  | Exercise Price |  | Life in Years
Options outstanding at January 3, 2021 |  | 557 | ​ | $ | 4.53 | ​ | ​
Granted |  | 123 | ​ |  | 12.99 | ​ | ​
Exercised | ​ | (181) | ​ | ​ | 4.63 | ​ | ​
Canceled, forfeited or expired | ​ | (51) | ​ | ​ | 4.21 | ​ | ​
Options outstanding at October 3, 2021 |  | 448 | ​ | $ | 6.85 | ​ | 7.4
Schedule of stock option valuation assumptions | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nine Months Ended | ​
​ |  | October 3, 2021 | ​ | September 27, 2020 | ​
Weighted-average fair value of options granted during the period | ​ | $ | 7.33 | ​ | $ | 1.79 | ​
Expected life (in years) | ​ |  | 5.6 | ​ |  | 5.1 | ​
Expected dividend | ​ | $ | — | ​ | $ | — | ​
Expected stock volatility | ​ |  | 64.02 | % |  | 55.02 | %
Risk-free interest rate | ​ |  | 0.9 | % |  | 0.9 | %
Schedule of unvested restricted stock activity | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ |  | ​ |  | ​ | ​ | ​ | Weighted
​ | ​ | ​ | ​ | ​ | ​ | ​ | Average
​ | ​ | ​ | ​ | ​ | ​ | ​ | Remaining
​ | ​ | Number of | ​ | Weighted Average | ​ | Contractual
(number of awards in thousands) |  | Awards |  | Award Date Fair Value |  | Life in Years
Unvested at January 3, 2021 |  | 475 | ​ | $ | 4.43 | ​ | ​
Granted |  | 53 | ​ |  | 13.25 | ​ | ​
Exercised/Released | ​ | (168) | ​ | ​ | 4.93 | ​ | ​
Canceled, forfeited or expired | ​ | (55) | ​ | ​ | 4.30 | ​ | ​
Unvested at October 3, 2021 |  | 305 | ​ | $ | 5.71 | ​ | 14.8

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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of employee stock purchase plans, including, but not limited to: (a) expected term, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References 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 (f)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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