Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands			3 Months Ended
	Dec. 30, 2018 USD ($)	Oct. 01, 2018 USD ($)	Mar. 30, 2019 USD ($)	Mar. 31, 2018 USD ($) shares	Dec. 29, 2018 USD ($)
Number of VIEs Consolidated			1
Accounts Receivable, Allowance for Credit Loss, Current			$ 300		$ 300
Number of Operating Segments			4
Number of Reportable Segments			2
Goodwill and Intangible Asset Impairment, Total		$ 0
Amortization of Debt Issuance Costs and Discounts, Total			$ 300	$ 0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax			200	$ (1,600)
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares				34,000
Revenue, Remaining Performance Obligation, Amount			16,800
Accounts Receivable, Credit Loss Expense (Reversal)			0
Contract with Customer, Liability, Total			0
Contract with Customer, Liability, Current			13,900		10,800
Deferred Profit			8,268		6,896
Accumulated Other Comprehensive Income (Loss), Net of Tax, Total			(30,664)		(25,880)
Assets, Total			1,106,197		1,134,002	[1]
Contract with Customer, Asset, after Allowance for Credit Loss, Total					0
Accounting Standards Update 2016-02 [Member]
Lease Assets	$ 30,700
Lease Liabilities	29,900
Cumulative Effect on Retained Earnings, Net of Tax, Total	10,200
Assets, Total	(500)
Liabilities, Total	$ (600)
Non-current Other Accrued Liabilities [Member]
Deferred Profit Recognized After Year One			$ 3,100		$ 2,000
Minimum [Member]
Standard Product Warranty Term			1 year
Maximum [Member]
Standard Product Warranty Term			3 years
Building [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life			30 years
Building [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life			40 years
Building Improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life			5 years
Building Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life			15 years
Machinery, Equipment and Software [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life			3 years
Machinery, Equipment and Software [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life			10 years
ALBS [Member]
Variable Interest Entity, Consolidated, Assets, Pledged, Total			$ 0

[1] Derived from December 29, 2018 audited financial statements