Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands		Total	Common Stock [Member]	Additional paid-in capital [Member]	Accumulated other comprehensive income (loss) [Member]	Retained earnings [Member]	Treasury Stock [Member]
Balance at Jan. 03, 2020		$ 350,251	$ 66	$ 244,935	$ (1,760)	$ 384,668	$ (277,658)
Balances (in shares) at Jan. 03, 2020			65,707,000				13,951,000
Employee stock purchase plan		1,791		1,536			$ 255
Employee stock purchase plan (in shares)							(24,000)
Exercise of stock options		4,940		1,996			$ 2,944
Exercise of stock options (in shares)							(284,000)
Amortization of unrecognized stock-based compensation		9,165		9,165
Purchase of treasury shares		(40,049)					$ (40,049)
Purchase of treasury shares (in shares)							636,000
Foreign currency translation adjustments		65			65
Grant of restricted stock units to settle accrued bonus		8,645		8,645
Settlement of restricted stock units		(15,263)		(1,460)		(4,538)	$ (9,265)
Settlement of restricted stock units (in shares)							(376,000)
Unrealized gain (loss) on investments		(237)			(237)
Dividends and dividend equivalent rights		(40,362)		511		(40,873)
Net income		82,552				82,552
Balance at Jan. 01, 2021		361,498	$ 66	265,328	(1,932)	421,809	$ (323,773)
Balances (in shares) at Jan. 01, 2021			65,707,000				13,903,000
Employee stock purchase plan		1,977		1,777			$ 200
Employee stock purchase plan (in shares)							(20,000)
Exercise of stock options		1,134		657			$ 477
Exercise of stock options (in shares)							(48,000)
Amortization of unrecognized stock-based compensation		9,296		9,296
Purchase of treasury shares		(7,000)					$ (7,000)
Purchase of treasury shares (in shares)							78,000
Foreign currency translation adjustments		14			14
Grant of restricted stock units to settle accrued bonus		7,637		7,637
Settlement of restricted stock units		(15,666)		(3,276)		(1,679)	$ (10,711)
Settlement of restricted stock units (in shares)							(322,000)
Unrealized gain (loss) on investments		(6)			(65)	59
Dividends and dividend equivalent rights		(43,021)		0		(43,021)
Net income		101,202				101,202
Balance at Dec. 31, 2021		417,065	$ 66	281,419	(1,983)	478,370	$ (340,807)
Balances (in shares) at Dec. 31, 2021			65,707,000				13,591,000
Employee stock purchase plan		$ 2,020		1,805			$ 215
Employee stock purchase plan (in shares)							(22,000)
Exercise of stock options (in shares)	[1]	0
Amortization of unrecognized stock-based compensation		$ 9,999		9,999
Purchase of treasury shares		(155,856)					$ (155,856)
Purchase of treasury shares (in shares)							1,756,000
Foreign currency translation adjustments		(1,604)			(1,604)
Grant of restricted stock units to settle accrued bonus		10,200		10,200
Settlement of restricted stock units		(12,904)		(2,421)		(1,392)	$ (9,091)
Settlement of restricted stock units (in shares)							(261,000)
Dividends and dividend equivalent rights		(50,498)				(50,498)
Net income		102,330				102,330
Balance at Dec. 30, 2022		$ 320,752	$ 66	$ 301,002	$ (3,587)	$ 528,810	$ (505,539)
Balances (in shares) at Dec. 30, 2022			65,707,000				15,064,000

[1] Does not include restricted stock or employee stock purchase plans.