Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Balance (in shares) at Jul. 01, 2018	52,071,293	33,822,823				21,258,790
Balance at Jul. 01, 2018	$ 520	$ 338	$ 341,783	$ 73,429	$ (200)	$ (100,966)	$ 314,904
Net income				51,312			51,312
Translation adjustment					(61)		(61)
Stock-based compensation (in shares)	409,676
Stock-based compensation	$ 4		2,624				2,628
Exercise of stock options (in shares)	268,234
Exercise of stock options	$ 3		362				365
Acquisition of Class A treasury stock (in shares)						1,124,948
Acquisition of Class A treasury stock						$ (13,405)	(13,405)
Other				330			330
Balance (in shares) at Dec. 30, 2018	52,749,203	33,822,823				22,383,738
Balance at Dec. 30, 2018	$ 527	$ 338	344,769	125,071	(261)	$ (114,371)	356,073
Balance (in shares) at Oct. 01, 2018	52,162,960	33,822,823				21,604,412
Balance at Oct. 01, 2018	$ 521	$ 338	343,038	57,283	(190)	$ (105,006)	295,984
Net income				68,578			68,578
Translation adjustment					(71)		(71)
Stock-based compensation (in shares)	408,009
Stock-based compensation	$ 4		1,669				1,673
Exercise of stock options (in shares)	178,234
Exercise of stock options	$ 2		62				64
Acquisition of Class A treasury stock (in shares)						779,326
Acquisition of Class A treasury stock						$ (9,365)	(9,365)
Other				(790)			(790)
Balance (in shares) at Dec. 30, 2018	52,749,203	33,822,823				22,383,738
Balance at Dec. 30, 2018	$ 527	$ 338	344,769	125,071	(261)	$ (114,371)	356,073
Balance (in shares) at Jun. 30, 2019	53,084,127	33,822,823				22,489,093
Balance at Jun. 30, 2019	$ 530	$ 338	349,319	108,525	(269)	$ (115,732)	342,711
Net income				58,881			58,881
Translation adjustment					16		16
Stock-based compensation (in shares)	444,792
Stock-based compensation	$ 4		4,041				$ 4,045
Exercise of stock options (in shares)	150,000						150,000
Exercise of stock options	$ 2		283				$ 285
Acquisition of Class A treasury stock (in shares)						370,863
Acquisition of Class A treasury stock						$ (5,030)	(5,030)
Balance (in shares) at Dec. 29, 2019	53,678,919	33,822,823				22,859,956
Balance at Dec. 29, 2019	$ 536	$ 338	353,643	167,406	(253)	$ (120,762)	400,908
Balance (in shares) at Sep. 29, 2019	53,216,294	33,822,823				22,491,206
Balance at Sep. 29, 2019	$ 532	$ 338	351,304	93,254	(269)	$ (115,763)	329,396
Net income				74,152			74,152
Translation adjustment					16		16
Stock-based compensation (in shares)	437,625
Stock-based compensation	$ 4		2,276				2,280
Exercise of stock options (in shares)	25,000
Exercise of stock options			63				63
Acquisition of Class A treasury stock (in shares)						368,750
Acquisition of Class A treasury stock						$ (4,999)	(4,999)
Balance (in shares) at Dec. 29, 2019	53,678,919	33,822,823				22,859,956
Balance at Dec. 29, 2019	$ 536	$ 338	$ 353,643	$ 167,406	$ (253)	$ (120,762)	$ 400,908