Note 6 - Restructuring - Activity Related to Restructuring Plans (Details) - USD ($) $ in Thousands		3 Months Ended		15 Months Ended
		Mar. 28, 2020	Mar. 30, 2019	Mar. 28, 2020
Accrued Restructuring		$ 7,610	$ 10,680	$ 10,680
Restructuring charges		940	1,341	940
Costs paid or otherwise settled			(3,508)	(741)
Accrued Restructuring		7,809	8,513	7,809
Employee Severance [Member]
Accrued Restructuring	[1]	160	1,814	1,814
Restructuring charges	[1]		(60)	949
Costs paid or otherwise settled	[1]		(1,540)	(135)
Accrued Restructuring	[1]	974	214	974
Lease Termination and Fixed Assets [Member]
Accrued Restructuring		6,585	8,630	8,630
Restructuring charges			1,409	47
Costs paid or otherwise settled			(1,875)	(405)
Accrued Restructuring		6,227	8,164	6,227
Software Contracts and Engineering Tools [Member]
Accrued Restructuring	[2]	0	218	218
Restructuring charges	[2]		0	0
Costs paid or otherwise settled	[2]		(83)	0
Accrued Restructuring	[2]	0	135	0
Other Restructuring [Member]
Accrued Restructuring	[3]	865	18	18
Restructuring charges	[3]		(8)	(56)
Costs paid or otherwise settled	[3]		(10)	(201)
Accrued Restructuring	[3]	$ 608	$ 0	$ 608

[1] Includes employee relocation and outplacement costs

[2] Includes cancellation of contracts, asset impairments, and accelerated depreciation on certain enterprise resource planning and customer relationship management systems

[3] Beginning in the second quarter of fiscal 2019, "Other" included termination fees on the cancellation of certain contracts under the Q2 2019 Sales Plan