| Note 6 - Capital Stock | 6 Months Ended | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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| Notes to Financial Statements | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Stockholders' Equity Note Disclosure [Text Block] | 
 Common shares Issued and outstanding: The issued and outstanding number of common shares included in shareholders’ equity consisted of the following: 
 
 Stock Options For more detailed information regarding the Company’s stock option arrangements, see Note  6of the consolidated financial statements within the Company’s Form 10-K for the fiscal period ended  December 31, 2017. The Company granted 335,929stock options during the threeand sixmonths period ended  July 1, 2018. A summary of stock option activity for the sixmonths period ended  July 1, 2018 is as follows: 
 During the  threemonth periods ended  July 1, 2018 and  July 2, 2017, the Company recorded stock-based compensation expense related to stock options and a corresponding increase in additional paid-in capital of $34and $11,respectively. During the sixmonth periods ended  July 1, 2018 and  July 2, 2017, the Company recorded stock-based compensation expense related to stock options and a corresponding increase in additional paid-in capital of $59and $23,respectively. Certain stock options outstanding have market conditions such that the awards are vested and exercisable only if the Company’s stock exceeds specified targets during the vesting period. If the market conditions are  notmet, the stock options will notvest and will expire. Restricted Stock Units For more detailed information regarding the Company’s Restricted Stock Units (“RSUs”) arrangements, see Note  6of the consolidated financial statements within the Company’s Form 10-K for the fiscal period ended  December 31, 2017. There were 25,000RSUs granted during the sixmonths ended  July 1, 2018. A summary of the RSUs activity for the sixmonth period ended  July 1, 2018 is as follows: 
 Certain RSUs outstanding have a market condition such that the awards are vested and issuable only if the market price of the Company’s stock meets or exceeds a specified target during the vesting period. If the market condition is  notmet, the RSUs will notvest and will be forfeited. Stock based compensation expense (recovery) recognized during the  threemonth periods ended  July 1, 2018 and  July 2, 2017 related to the RSUs was $43and ( $18), respectively. The recovery of stock based compensation was due to the reversal of unvested RSUs for terminated employees. Stock based compensation recognized during the sixmonth periods ended  July 1, 2018 and  July 2, 2017 related to the RSUs was $144and $173,respectively. | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||