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. 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
Restricted stock units and stock options surrendered for withholding taxes payable		(76)			(76)
Cash dividends declared			(578)		(578)
Vesting of restricted stock units (in shares)	22
Vesting of restricted stock units	$ 22	(22)			0
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
Balance (in shares) at Oct. 03, 2020	19,304
Balance at Oct. 03, 2020	$ 19,304	76,387	171,068	(1,956)	264,803
Net earnings			8,143		8,143
Stock options exercised, net (in shares)	10
Stock options exercised, net	$ 10	118			128
Compensation expense associated with stock-based plans		224			224
Restricted stock units and stock options surrendered for withholding taxes payable		(13)			(13)
Cash dividends declared			(29,551)		(29,551)
Balance (in shares) at Jan. 02, 2021	19,314
Balance at Jan. 02, 2021	$ 19,314	76,716	149,660	(1,956)	243,734
Balance (in shares) at Oct. 03, 2020	19,304
Balance at Oct. 03, 2020	$ 19,304	76,387	171,068	(1,956)	264,803
Net earnings					$ 41,458
Stock options exercised, net (in shares)					48
Balance (in shares) at Jul. 03, 2021	19,358
Balance at Jul. 03, 2021	$ 19,358	77,780	181,814	(1,956)	$ 276,996
Balance (in shares) at Jan. 02, 2021	19,314
Balance at Jan. 02, 2021	$ 19,314	76,716	149,660	(1,956)	243,734
Net earnings			14,920		14,920
Stock options exercised, net (in shares)	2
Stock options exercised, net	$ 2	47			49
Compensation expense associated with stock-based plans		710			710
Restricted stock units and stock options surrendered for withholding taxes payable		(97)			(97)
Cash dividends declared			(580)		(580)
Vesting of restricted stock units (in shares)	25
Vesting of restricted stock units	$ 25	(25)			0
Balance (in shares) at Apr. 03, 2021	19,341
Balance at Apr. 03, 2021	$ 19,341	77,351	164,000	(1,956)	258,736
Net earnings			18,395		18,395
Stock options exercised, net (in shares)	17
Stock options exercised, net	$ 17	240			257
Compensation expense associated with stock-based plans		240			240
Restricted stock units and stock options surrendered for withholding taxes payable		(51)			(51)
Cash dividends declared			(581)		(581)
Balance (in shares) at Jul. 03, 2021	19,358
Balance at Jul. 03, 2021	$ 19,358	$ 77,780	$ 181,814	$ (1,956)	$ 276,996