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Stock-Based Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended					6 Months Ended
	Mar. 30, 2021	Dec. 29, 2020	Mar. 31, 2020	Mar. 31, 2020	Dec. 29, 2019	Mar. 30, 2021	Mar. 31, 2020	Sep. 29, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 276			$ 149		$ 276	$ 149
Stock options granted, shares						90,000
Stock options granted, exercise price	$ 3.54					$ 3.54		$ 3.56
Stock options exercised, shares			15,646	15,646		43,330
Proceeds from stock option exercises						$ 96
Stock issued against stock options exercised				2,413
Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options exercised, shares	35,346	7,984			2,413
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Aggregate Intrinsic Value, Outstanding	$ 511					511
Aggregate Intrinsic Value, Exercisable	338					338
Remaining total unrecognized compensation cost related to unvested stock-based arrangements	$ 150					150
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition	1 year 6 months
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining total unrecognized compensation cost related to unvested stock-based arrangements	$ 98					$ 98
Employee service share-based compensation, nonvested awards, total compensation cost not yet recognized, period for recognition	7 months 6 days
Restricted Stock [Member] \| Restricted stock units vest three years following the grant date [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, shares						46,336
Stock options granted, per-share weighted average fair value						$ 1.54
Restricted Stock [Member] \| Restricted stock units vested on their grant date [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, shares						14,000
Stock options granted, per-share weighted average fair value						$ 1.67
Restricted Stock [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, shares						60,336
Restricted Stock One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted, shares
Director [Member] \| 2018 Plan [Member] \| Common Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, shares						12,948
Stock options granted, per-share weighted average fair value						$ 2.78
Chief Executive Officer [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, shares						90,000
Stock options granted, exercise price	$ 2.33					$ 2.33
Stock options granted, per-share weighted average fair value						$ 1.22
Chief Executive Officer [Member] \| Performance shares [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options granted, shares						10,000
Stock options granted, per-share weighted average fair value						$ 2.77