5. Stock Option Plan: Schedule of Stock Option Plan Activity (Details) shares in Thousands	3 Months Ended
Mar. 29, 2019 $ / shares shares
Text Block [Abstract]
Outstanding at beginning of the period \| shares	1,597
Outstanding at beginning of year, weighted average exercise price \| $ / shares	$ 0.65
Granted \| shares	165
Granted, weighted average exercise price \| $ / shares	$ 0.80
Exercised \| shares	(130)
Exercised, weighted average exercise price \| $ / shares	$ 0.17
Forfeited or expired \| shares	(40)
Forfeited or expired, weighted average exercise price \| $ / shares	$ 0.66
Outstanding at beginning of the period \| shares	1,592
Outstanding at beginning of the period, weighted average exercise price \| $ / shares	$ 0.71
Exercisable as of end of the period \| shares	1,164
Exercisable as of end of the period, weighted average exercise price \| $ / shares	$ 0.61

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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For presentations that combine terminations, 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 or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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