Note 14 - Restructuring and Asset Impairment Charges - Restructuring Activities (Details) - USD ($) $ in Thousands	3 Months Ended			12 Months Ended		27 Months Ended
	Apr. 01, 2018	Apr. 02, 2017	Jan. 01, 2017	Dec. 31, 2017	Jan. 01, 2017	Apr. 01, 2018
Total restructuring charge		$ 7,300	$ 19,800
Employee Severance [Member]
Total restructuring charge		600				$ 10,652
Cost incurred	$ 917			$ 6,633	$ 1,451
Balance	1,651					1,651
Fixed Asset Impairment [Member]
Total restructuring charge		3,300				11,319
Cost incurred	0			3,300	8,019
Balance	0					0
Other Restructuring [Member]
Total restructuring charge		$ 3,400				5,116
Cost incurred	0			$ 5,089	$ 27
Balance	$ 0					$ 0