Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ 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. 01, 2021	$ 361,498	$ 66	$ 265,328	$ (1,932)	$ 421,809	$ (323,773)
Balances (in shares) at Jan. 01, 2021		65,707				13,903
Employee stock purchase plan	1,023		909			$ 114
Employee stock purchase plan (in shares)						(12)
Amortization of unrecognized stock-based compensation	5,676		5,676
Purchase of treasury stock	(7,000)					$ (7,000)
Purchase of treasury stock (in shares)						79
Foreign currency translation adjustments	211			211
Grant of restricted stock units to settle accrued bonus	7,637		7,637
Settlement of restricted stock units	(15,666)		(3,269)		(1,679)	$ (10,718)
Settlement of restricted stock units (in shares)						(322)
Unrealized gain on investments	(4)			(65)	61
Dividends and dividend equivalent rights	(21,856)				(21,856)
Net income	56,248				56,248
Balance at Jul. 02, 2021	387,767	$ 66	276,281	(1,786)	454,583	$ (341,377)
Balances (in shares) at Jul. 02, 2021		65,707				13,648
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				13,903
Net income	80,822
Balance at Oct. 01, 2021	404,989	$ 66	279,250	(2,052)	468,578	$ (340,853)
Balances (in shares) at Oct. 01, 2021		65,707				13,595
Balance at Jul. 02, 2021	387,767	$ 66	276,281	(1,786)	454,583	$ (341,377)
Balances (in shares) at Jul. 02, 2021		65,707				13,648
Employee stock purchase plan	518		471			$ 47
Employee stock purchase plan (in shares)						(5)
Exercise of stock options	1,135		658			$ 477
Exercise of stock options (in shares)						(48)
Amortization of unrecognized stock-based compensation	1,840		1,840
Foreign currency translation adjustments	(266)			(266)
Dividends and dividend equivalent rights	(10,579)				(10,579)
Net income	24,574				24,574
Balance at Oct. 01, 2021	404,989	$ 66	279,250	(2,052)	468,578	$ (340,853)
Balances (in shares) at Oct. 01, 2021		65,707				13,595
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				13,591
Employee stock purchase plan	1,070		961			$ 109
Employee stock purchase plan (in shares)						(12)
Amortization of unrecognized stock-based compensation	5,939		5,939
Purchase of treasury stock	(111,843)					$ (111,843)
Purchase of treasury stock (in shares)						1,273
Foreign currency translation adjustments	(1,660)			(1,660)
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)						(262)
Dividends and dividend equivalent rights	(25,737)				(25,737)
Net income	55,364				55,364
Balance at Jul. 01, 2022	337,494	$ 66	296,098	(3,643)	506,605	$ (461,632)
Balances (in shares) at Jul. 01, 2022		65,707				14,590
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				13,591
Net income	79,806
Balance at Sep. 30, 2022	319,800	$ 66	298,589	(5,136)	518,631	$ (492,350)
Balances (in shares) at Sep. 30, 2022		65,707				14,918
Balance at Jul. 01, 2022	337,494	$ 66	296,098	(3,643)	506,605	$ (461,632)
Balances (in shares) at Jul. 01, 2022		65,707				14,590
Employee stock purchase plan	557		492			$ 65
Employee stock purchase plan (in shares)						(7)
Amortization of unrecognized stock-based compensation	1,999		1,999
Purchase of treasury stock	(30,783)					$ (30,783)
Purchase of treasury stock (in shares)						335
Foreign currency translation adjustments	(1,493)			(1,493)
Dividends and dividend equivalent rights	(12,416)				(12,416)
Net income	24,442				24,442
Balance at Sep. 30, 2022	$ 319,800	$ 66	$ 298,589	$ (5,136)	$ 518,631	$ (492,350)
Balances (in shares) at Sep. 30, 2022		65,707				14,918