Note 13 - Income (Loss) Per Share - Distributed and Undistributed Earnings (Details) - $ / shares	12 Months Ended
	Dec. 30, 2018	Dec. 31, 2017	Jan. 01, 2017
Distributed earnings (in dollars per share)	$ 0.26	$ 0.25	$ 0.22
Undistributed earnings (in dollars per share)	0.58	0.61	0.61
(in dollars per share)	0.84	0.86	0.83
Distributed earnings (in dollars per share)	0.26	0.25	0.22
Undistributed earnings (in dollars per share)	0.58	0.61	0.61
(in dollars per share)	$ 0.84	$ 0.86	$ 0.83