Note 9 - Pensions - Components of Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 27, 2015	Jun. 28, 2014	Jun. 27, 2015	Jun. 28, 2014
United States Pension Plan of US Entity [Member]
Service cost	$ 250	$ 150	$ 500	$ 300
Interest cost	1,031	971	2,062	1,942
Expected return on plan assets	(916)	(1,411)	(1,832)	(2,822)
Amortization of net loss	290	137	580	274
Total cost (credit) of the plan	655	(153)	1,310	(306)
Net periodic benefit cost (credit)	655	(153)	1,310	(306)
Foreign Pension Plan [Member]
Service cost	315	311	630	622
Interest cost	513	592	1,026	1,183
Expected return on plan assets	(601)	(573)	(1,201)	(1,146)
Amortization of net loss	62	47	123	95
Total cost (credit) of the plan	289	377	578	754
Net periodic benefit cost (credit)	$ 289	$ 377	$ 578	$ 754