Note 2 - Correction of Immaterial Errors - Effects of Adjustments to Correct Immaterial Errors, Balance Sheet (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Jan. 02, 2016	Dec. 27, 2014	Dec. 28, 2013
Other long-term liabilities	$ 20,366	$ 17,755
Total shareholders’ equity	$ 814,931	739,252	$ 724,319	$ 684,888
Scenario, Previously Reported [Member]
Other long-term liabilities		12,809
Total shareholders’ equity		744,198	727,665	686,916
Restatement Adjustment [Member]
Other long-term liabilities		4,946
Total shareholders’ equity		$ (4,946)	$ (3,346)	$ (2,028)