Note 11 - Income (Loss) Per Share - Calculation of Income (Loss) Per Shares (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended											12 Months Ended
	Dec. 31, 2017	[1]	Oct. 01, 2017	Jul. 02, 2017	Apr. 02, 2017	[2]	Jan. 01, 2017	[3]	Oct. 02, 2016	Jul. 03, 2016	Apr. 03, 2016	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Net income	$ 4,322		$ 19,439	$ 20,938	$ 8,547		$ 4,707		$ 15,904	$ 20,657	$ 12,894	$ 53,246	$ 54,162	$ 72,418
Shares for Basic Earnings Per Share (in shares)												61,996	65,098	66,027
Dilutive Effect of Stock Options (in shares)												44	38	48
Shares for Diluted Earnings Per Share (in shares)												62,040	65,136	66,075
Participating Securities [Member]
Net income												$ 400	$ 400	$ 1,600
Weighted Average Shares Outstanding (in shares)												61,528	64,593	64,557
Participating Securities (in shares)												468	505	1,470

[1] Results for the fourth quarter of 2017 include tax charges of $15.2 million as a result of the recently enacted U.S. Tax Cuts and Jobs Act.

[2] Results for the first quarter of 2017 include restructuring and asset impairment charges of $7.3 million.

[3] Results for the fourth quarter of 2016 include restructuring and asset impairment charges of $19.8 million.