Condensed Consolidated Statements of Operations shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 02, 2022 USD ($) $ / shares shares	Jul. 03, 2021 USD ($) $ / shares shares	Jul. 02, 2022 USD ($) $ / shares shares	Jul. 03, 2021 USD ($) $ / shares shares
Income Statement [Abstract]
Revenues	$ 401,959	$ 355,476	$ 744,603	$ 654,297
Costs and expenses:
Operating	251,554	219,275	485,761	418,310
Selling	68,155	58,836	128,951	111,523
General and administrative	30,055	23,622	59,050	48,973
Depreciation and amortization	13,515	13,702	27,302	27,160
Gain on sale of assets, net	(2,052)	(1,983)	(2,950)	(2,667)
Total costs and expenses	361,227	313,452	698,114	603,299
Income from operations	40,732	42,024	46,489	50,998
Other income (expense):
Interest expense	(1,703)	(1,370)	(3,148)	(2,644)
Interest income	159	53	186	122
Other, net	(2,533)	(1,200)	(4,870)	(3,250)
Income before income taxes	36,655	39,507	38,657	45,226
Income taxes	9,870	10,964	10,090	12,256
Net income	$ 26,785	$ 28,543	$ 28,567	$ 32,970
Net income per share:*
Net income per share, basic | $ / shares	$ 0.61	$ 0.63	$ 0.64	$ 0.73
Net income per share, diluted | $ / shares	$ 0.58	$ 0.60	$ 0.61	$ 0.69
Weighted-average shares outstanding:
Weighted-average shares outstanding, basic | shares	44,052	45,205	44,333	45,443
Weighted-average shares outstanding, diluted | shares	46,464	47,489	46,650	47,702
Stock split, conversion ratio			2