Consolidated Statements of Shareholders' Equity - USD ($) $ in Thousands	Total	Cumulative Effect, Period of Adoption, Adjustment [Member]	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative Effect, Period of Adoption, Adjustment [Member]
Beginning Balance at Jan. 02, 2018	$ 258,729			$ 68,904	$ 189,825
Beginning Balance (in shares) at Jan. 02, 2018			20,485,000
Exercise of stock options	$ 26,140		$ 36,520	(10,380)
Exercise of stock options (in shares)	876,000		876,000
Issuance of restricted stock units	$ (383)		$ 2,383	(2,766)
Issuance of restricted stock units (in shares)			102,000
Repurchase and retirement of common stock	(20,331)		$ (38,903)		18,572
Repurchase and retirement of common stock (in shares)			(405,000)
Stock-based compensation	8,584			8,584
Ending Balance at Jan. 01, 2019	$ 309,221	$ (4,598)		64,342	244,879	$ (4,598)
Accounting Standards Update Extensible List	us-gaap:AccountingStandardsUpdate201602Member
Dividends paid or payable	$ (9,730)				(9,730)
Net income (loss)	50,810				50,810
Ending Balance (in shares) at Jan. 01, 2019			21,058,000
Issuance of restricted stock units (in shares)			(102,000)
Exercise of stock options	$ 1,066		$ 1,422	(356)
Exercise of stock options (in shares)	37,000		37,000
Issuance of restricted stock units	$ (1,014)		$ 5,122	(6,136)
Issuance of restricted stock units (in shares)			127,000
Repurchase and retirement of common stock	(82,760)		$ (6,544)		(76,216)
Repurchase and retirement of common stock (in shares)			(2,073,000)
Stock-based compensation	9,212			9,212
Ending Balance at Dec. 31, 2019	$ 290,287	$ 19,502		67,062	223,225	$ 19,502
Accounting Standards Update Extensible List	us-gaap:AccountingStandardsUpdate201602Member
Dividends paid or payable	$ (10,178)				(10,178)
Net income (loss)	45,238				45,238
Ending Balance (in shares) at Dec. 31, 2019			19,149,000
Issuance of restricted stock units (in shares)			(127,000)
Exercise of stock options	$ 27		$ 36	(9)
Exercise of stock options (in shares)	1,000		1,000
Issuance of restricted stock units	$ (817)		$ 7,728	(8,545)
Issuance of restricted stock units (in shares)			163,000
Repurchase and retirement of common stock	$ (15,014)		$ (71,712)		56,698
Repurchase and retirement of common stock (in shares)	(500,000)		(495,000)
Stock-based compensation	$ 9,820			9,820
Ending Balance at Dec. 29, 2020	293,788			71,722	222,066
Adjustment to dividends previously accrued	28				28
Net income (loss)	(57,885)				$ (57,885)
Ending Balance (in shares) at Dec. 29, 2020			22,318,000
Issuance of common stock and warrant, net	$ 67,342		$ 63,948	$ 3,394
Issuance of common stock and warrant, net (in shares)			3,500,000		3,500,000
Issuance of restricted stock units (in shares)			(163,000)