Note 7 - Fair Value of Assets and Liabilities (Tables)

12 Months Ended

Dec. 30, 2017

Notes Tables

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

	Fair Value Measurements Using
(in thousands )	Level 1		Level 2		Level 3		Total
Investment in Polytronics	$	10,993	$	—	$	—	$	10,993

	Fair Value Measurements Using
(in thousands )	Level 1		Level 2		Level 3		Total
Investment in Polytronics	$	10,435	$	—	$	—	$	10,435

Fair Value, by Balance Sheet Grouping [Table Text Block]

	2017				2016
(in thousands )	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Euro Senior Notes, Series A due 2023	$	139,623	$	138,294	$	122,313	$	122,586
Euro Senior Notes, Series B due 2028		113,369		111,579		95,314		99,230
U .S. Senior Notes, Series A due 2022		25,000		24,737		25,000		24,746
U .S. Senior Notes, Series B due 2027		100,000		99,992		100,000		98,660

Details of Impairment of Long-Lived Assets Held and Used by Asset [Table Text Block]

	Year Ended December 31, 2016				As of December 31, 2016
(in thousands )	Impairment Charge		Fair Value Measurement (Level 3)		Net Book Value
Goodwill	$	8,794	$	—	$	—
Other intangible assets		6,015		680		660
Total	$	14,809	$	680	$	660

Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Table Text Block]

(in thousands , except rates data )	Fair Value		Valuation Technique	Unobservable Inputs	Rates
Tradename	$	680	Relief from royalty	Discount rate:		18%
				R oyalty rate:		1%
Customer relationships	$	—	Excess earnings	Discount rate:		18%
				Attrition rate:		5%