Note 9 - Plant Restructuring - Restructuring Reserve (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Dec. 28, 2019	Sep. 28, 2019	Jun. 29, 2019	Dec. 29, 2018	Sep. 29, 2018	Jun. 30, 2018	Dec. 28, 2019	Dec. 29, 2018
Balance			$ 226				$ 226
Quarter charge (credit)	$ 793	$ 1,146	4,806	$ 1,396	$ 845	38
Cash payments/write offs							(6,891)	(904)
Quarter charge (credit)	793	1,146	4,806	1,396	845	38
Balance	80			1,375			80	1,375
Employee Severance [Member]
Balance			225				225
Quarter charge (credit)	28	386	586	378	845	110
Cash payments/write offs							(1,145)	(976)
Quarter charge (credit)	28	386	586	378	845	110
Balance	80			357			80	357
Other Restructuring [Member]
Balance			1				1
Quarter charge (credit)	765	760	4,220	1,018		(72)
Cash payments/write offs							(5,746)	72
Quarter charge (credit)	765	$ 760	$ 4,220	1,018		$ (72)
Balance				$ 1,018				$ 1,018