CONDENSED CONSOLIDATED STATEMENT of CHANGES in STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Common Stock	Additional Paid-In Capital	Accumulated Deficit	Treasury Stock, at cost	Total
Beginning Balance (shares) at Sep. 30, 2019	10,338,548
Beginning Balance at Sep. 30, 2019	$ 103	$ 48,001	$ (15,275)	$ (1,589)	$ 31,240
Net income (loss)			1,189		1,189
Stock-based compensation		152			152
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes (shares)	6,367
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes		$ (24)			$ (24)
Exercise of stock options, net of shares surrendered (shares)	24,000	130,000			130,000
Employee stock plan purchases (shares)	6,449
Employee stock plan purchases		$ 40			$ 40
Ending Balance at Dec. 27, 2019	$ 103	48,299	(14,086)	(1,589)	32,727
Ending Balance (shares) at Dec. 27, 2019	10,375,364
Beginning Balance (shares) at Sep. 30, 2019	10,338,548
Beginning Balance at Sep. 30, 2019	$ 103	48,001	(15,275)	(1,589)	31,240
Net income (loss)					$ 4,826
Exercise of stock options, net of shares surrendered (shares)					30,500
Ending Balance at Jun. 26, 2020	$ 104	48,676	(10,449)	(1,589)	$ 36,742
Ending Balance (shares) at Jun. 26, 2020	10,430,726
Beginning Balance (shares) at Dec. 27, 2019	10,375,364
Beginning Balance at Dec. 27, 2019	$ 103	48,299	(14,086)	(1,589)	32,727
Net income (loss)			1,523		1,523
Stock-based compensation		185			185
Restricted stock vested, net of shares withheld for payment of taxes (shares)	4,663
Restricted stock vested, net of shares withheld for payment of taxes		(33)			(33)
Restricted stock units vested, net of shares withheld for payment of taxes (shares)	10,089
Restricted stock units vested, net of shares withheld for payment of taxes		(35)			(35)
Employee stock plan purchases (shares)	2,000
Employee stock plan purchases		8			8
Ending Balance at Mar. 27, 2020	$ 103	48,424	(12,563)	(1,589)	34,375
Ending Balance (shares) at Mar. 27, 2020	10,392,116
Net income (loss)			2,114		2,114
Stock-based compensation		189			189
Restricted stock vested, net of shares withheld for payment of taxes (shares)	25,576
Restricted stock vested, net of shares withheld for payment of taxes		(6)			(6)
Exercise of stock options, net of shares surrendered (shares)	4,500
Exercise of stock options, net of shares surrendered		23			23
Employee stock plan purchases (shares)	8,534
Employee stock plan purchases	$ 1	46			47
Ending Balance at Jun. 26, 2020	$ 104	48,676	(10,449)	(1,589)	$ 36,742
Ending Balance (shares) at Jun. 26, 2020	10,430,726
Beginning Balance (shares) at Sep. 30, 2020	10,500,726				10,500,726
Beginning Balance at Sep. 30, 2020	$ 105	49,161	(8,522)	(1,589)	$ 39,155
Net income (loss)			1,537		1,537
Stock-based compensation		242			242
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes (shares)	57,455
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes	$ 1	(401)			(400)
Exercise of stock options, net of shares surrendered (shares)	14,000
Exercise of stock options, net of shares surrendered		68			68
Employee stock plan purchases (shares)	5,852
Employee stock plan purchases		45			45
Ending Balance at Jan. 01, 2021	$ 106	49,115	(6,985)	(1,589)	$ 40,647
Ending Balance (shares) at Jan. 01, 2021	10,578,033
Beginning Balance (shares) at Sep. 30, 2020	10,500,726				10,500,726
Beginning Balance at Sep. 30, 2020	$ 105	49,161	(8,522)	(1,589)	$ 39,155
Net income (loss)					$ 2,215
Exercise of stock options, net of shares surrendered (shares)					18,375
Ending Balance at Jul. 02, 2021	$ 106	49,514	(6,307)	(1,589)	$ 41,724
Ending Balance (shares) at Jul. 02, 2021	10,620,378				10,620,378
Beginning Balance (shares) at Jan. 01, 2021	10,578,033
Beginning Balance at Jan. 01, 2021	$ 106	49,115	(6,985)	(1,589)	$ 40,647
Net income (loss)			(348)		(348)
Stock-based compensation		226			226
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes (shares)	27,603
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes		(85)			(85)
Employee stock plan purchases (shares)	4,572
Employee stock plan purchases		49			49
Ending Balance at Apr. 02, 2021	$ 106	49,305	(7,333)	(1,589)	40,489
Ending Balance (shares) at Apr. 02, 2021	10,610,208
Net income (loss)			1,026		1,026
Stock-based compensation		182			182
Vested restricted stock and restricted stock units, net of shares withheld for payment of taxes (shares)	5,795
Exercise of stock options, net of shares surrendered (shares)	4,375
Exercise of stock options, net of shares surrendered		27			27
Ending Balance at Jul. 02, 2021	$ 106	$ 49,514	$ (6,307)	$ (1,589)	$ 41,724
Ending Balance (shares) at Jul. 02, 2021	10,620,378				10,620,378