Earnings Per Share: (Details) - shares	3 Months Ended	9 Months Ended
Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Earnings Per Share:
Denominator for basic EPS - weighted average common shares	3,808,863	3,886,473	3,829,329	3,864,077
Dilutive shares associated with option plans	256,438	277,866	282,989	276,739
Denominator for diluted EPS - weighted average common shares and dilutive potential common shares	4,065,301	4,164,339	4,112,318	4,140,816
Options excluded from EPS calculation - anti-dilutive (in shares)	7,146	6,116	6,782	15,428

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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-Publisher FASB
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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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