Note 18 - Quarterly Data and Share Information (Unaudited) (Details) - Consolidated Financial Data - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended											12 Months Ended
	Jan. 03, 2016	[1]	Oct. 04, 2015	Jul. 05, 2015	Apr. 05, 2015	Dec. 28, 2014	[1]	Sep. 28, 2014	[2]	Jun. 29, 2014	Mar. 30, 2014	Jan. 03, 2016		Dec. 28, 2014		Dec. 29, 2013
Note 18 - Quarterly Data and Share Information (Unaudited) (Details) - Consolidated Financial Data [Line Items]
Net sales (in Dollars)	$ 246,636		$ 254,686	$ 263,637	$ 236,904	$ 272,096		$ 252,191		$ 260,624	$ 218,992	$ 1,001,863	[3]	$ 1,003,903	[3]	$ 959,989	[3]
Gross profit (in Dollars)	98,239		97,966	101,252	85,432	91,361		83,595		90,385	74,686	382,889		340,027		341,109
Net income (in Dollars)	$ 18,247		$ 20,127	$ 21,722	$ 12,322	$ 8,088		$ (376)		$ 13,071	$ 4,025	$ 72,418		$ 24,808		$ 48,255
Basic income per share	$ 0.28		$ 0.31	$ 0.33	$ 0.19	$ 0.12		$ (0.01)		$ 0.20	$ 0.06	$ 1.10		$ 0.37		$ 0.73
Diluted income per share	0.28		0.31	0.33	0.19	0.12		(0.01)		0.20	0.06	1.10		0.37		$ 0.73
Maximum [Member]
Share prices
Share price	24.44		27.17	25.59	21.38	16.74		19.41		21.13	22.46	24.44	[1]	16.74	[1]
Minimum [Member]
Share prices
Share price	$ 17.89		$ 22.13	$ 19.86	$ 15.13	$ 12.98		$ 15.72		$ 17.11	$ 18.63	$ 17.89	[1]	$ 12.98	[1]

[1] Results for the fourth quarter of 2014 include debt retirement expenses of $12.0 million.

[2] Results for the third quarter of 2014 include restructuring and asset impairment charges of $12.4 million.

[3] Revenue attributed to geographic areas is based on the location of the customer.