Consolidated Statements of Shareholders' Equity (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Sep. 29, 2018	19,223
Balance at Sep. 29, 2018	$ 19,223	$ 72,852	$ 151,084	$ (1,494)	$ 241,665
Net earnings			4,126		4,126
Compensation expense associated with stock-based plans		174			174
Cash dividends declared			(576)		(576)
Restricted stock units and stock options surrendered for withholding taxes payable		(7)			(7)
Balance (in shares) at Dec. 29, 2018	19,223
Balance at Dec. 29, 2018	$ 19,223	73,019	154,634	(1,494)	245,382
Balance (in shares) at Sep. 29, 2018	19,223
Balance at Sep. 29, 2018	$ 19,223	72,852	151,084	(1,494)	241,665
Net earnings					7,365
Balance (in shares) at Jun. 29, 2019	19,252
Balance at Jun. 29, 2019	$ 19,252	73,849	156,717	(1,494)	248,324
Balance (in shares) at Dec. 29, 2018	19,223
Balance at Dec. 29, 2018	$ 19,223	73,019	154,634	(1,494)	245,382
Net earnings			1,049		1,049
Compensation expense associated with stock-based plans		845			845
Cash dividends declared			(578)		(578)
Vesting of restricted stock units (in shares)	29
Vesting of restricted stock units	$ 29	(29)
Restricted stock units and stock options surrendered for withholding taxes payable		(168)			(168)
Balance (in shares) at Mar. 30, 2019	19,252
Balance at Mar. 30, 2019	$ 19,252	73,667	155,105	(1,494)	246,530
Net earnings			2,190		2,190
Compensation expense associated with stock-based plans		182			182
Cash dividends declared			(578)		(578)
Balance (in shares) at Jun. 29, 2019	19,252
Balance at Jun. 29, 2019	$ 19,252	73,849	156,717	(1,494)	248,324
Balance (in shares) at Sep. 28, 2019	19,261
Balance at Sep. 28, 2019	$ 19,261	74,632	154,372	(2,248)	246,017
Net earnings			555		555
Compensation expense associated with stock-based plans		186			186
Cash dividends declared			(578)		(578)
Balance (in shares) at Dec. 28, 2019	19,261
Balance at Dec. 28, 2019	$ 19,261	74,818	154,349	(2,248)	246,180
Balance (in shares) at Sep. 28, 2019	19,261
Balance at Sep. 28, 2019	$ 19,261	74,632	154,372	(2,248)	246,017
Net earnings					11,583
Balance (in shares) at Jun. 27, 2020	19,283
Balance at Jun. 27, 2020	$ 19,283	75,811	164,220	(2,248)	257,066
Balance (in shares) at Dec. 28, 2019	19,261
Balance at Dec. 28, 2019	$ 19,261	74,818	154,349	(2,248)	246,180
Net earnings			4,364		4,364
Compensation expense associated with stock-based plans		941			941
Cash dividends declared			(578)		(578)
Vesting of restricted stock units (in shares)	22
Vesting of restricted stock units	$ 22	(22)
Restricted stock units and stock options surrendered for withholding taxes payable		(76)			(76)
Balance (in shares) at Mar. 28, 2020	19,283
Balance at Mar. 28, 2020	$ 19,283	75,661	158,135	(2,248)	250,831
Net earnings			6,664		6,664
Compensation expense associated with stock-based plans		150			150
Cash dividends declared			(579)		(579)
Balance (in shares) at Jun. 27, 2020	19,283
Balance at Jun. 27, 2020	$ 19,283	$ 75,811	$ 164,220	$ (2,248)	$ 257,066