CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Shares	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Balance at Dec. 31, 2018	$ 368,255	$ 423,856	$ 46,018	$ (79,092)	$ (22,527)
Balance (in shares) at Dec. 31, 2018		34,886
Consolidated net income	31,556			31,556
Common shares issued for a business combination	10,900		10,900
Common shares issued for business combination (in shares)		124
Common shares issued under stock plans	425		425
Common shares issued under stock plans (in shares)		245
Common shares withheld for taxes on vested stock awards	(6,839)		(6,839)
Common shares withheld for taxes on vested stock awards (in shares)		(85)
Repurchases of common shares	(6,684)		(6,684)
Repurchases of common shares (in shares)		(81)
Share-based compensation	7,348		7,348
Other comprehensive income (loss), net of tax	(2,084)				(2,084)
Balance at Sep. 27, 2019	402,877	$ 423,856	51,168	(47,536)	(24,611)
Balance (in shares) at Sep. 27, 2019		35,089
Balance at Jun. 28, 2019	386,182	$ 423,856	41,065	(56,459)	(22,280)
Balance (in shares) at Jun. 28, 2019		34,972
Consolidated net income	8,923			8,923
Common shares issued for a business combination	10,900		10,900
Common shares issued for business combination (in shares)		124
Common shares issued under stock plans	425		425
Common shares issued under stock plans (in shares)		36
Common shares withheld for taxes on vested stock awards	(120)		(120)
Common shares withheld for taxes on vested stock awards (in shares)		(1)
Repurchases of common shares	(3,345)		(3,345)
Repurchases of common shares (in shares)		(42)
Share-based compensation	2,243		2,243
Other comprehensive income (loss), net of tax	(2,331)				(2,331)
Balance at Sep. 27, 2019	402,877	$ 423,856	51,168	(47,536)	(24,611)
Balance (in shares) at Sep. 27, 2019		35,089
Balance at Dec. 31, 2019	417,172	$ 423,856	49,748	(38,319)	(18,113)
Balance (in shares) at Dec. 31, 2019		35,052
Consolidated net income	31,865			31,865
Common shares issued under stock plans	179		179
Common shares issued under stock plans (in shares)		264
Common shares withheld for taxes on vested stock awards	(8,302)		(8,302)
Common shares withheld for taxes on vested stock awards (in shares)		(91)
Repurchases of common shares	(5,500)		(5,500)
Repurchases of common shares (in shares)		(65)
Share-based compensation	16,072		16,072
Other comprehensive income (loss), net of tax	(237)				(237)
Balance at Oct. 02, 2020	451,249	$ 423,856	52,197	(6,454)	(18,350)
Balance (in shares) at Oct. 02, 2020		35,160
Balance at Jul. 03, 2020	431,898	$ 423,856	45,338	(14,712)	(22,584)
Balance (in shares) at Jul. 03, 2020		35,155
Consolidated net income	8,258			8,258
Common shares issued under stock plans (in shares)		8
Common shares withheld for taxes on vested stock awards	(366)		(366)
Common shares withheld for taxes on vested stock awards (in shares)		(3)
Share-based compensation	7,225		7,225
Other comprehensive income (loss), net of tax	4,234				4,234
Balance at Oct. 02, 2020	$ 451,249	$ 423,856	$ 52,197	$ (6,454)	$ (18,350)
Balance (in shares) at Oct. 02, 2020		35,160