Note 8 - Benefit Plans - Benefit Plan Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 30, 2017	Dec. 31, 2016	Jan. 02, 2016
Components of net periodic benefit cost:
Service cost	$ 2,037	$ 1,509	$ 1,574
Interest cost	1,887	1,662	4,828
Expected return on plan assets	(1,990)	(1,935)	(5,095)
Amortization of losses	337	306	1,091
Net periodic benefit cost	2,271	1,542	2,398
Curtailment/Settlement loss (gain)	(25)	(36)	29,928
Total expense (income) for the year	$ 2,246	$ 1,506	32,326
UNITED STATES
Components of net periodic benefit cost:
Service cost			750
Interest cost			3,093
Expected return on plan assets			(2,749)
Amortization of losses			870
Net periodic benefit cost			1,964
Curtailment/Settlement loss (gain)			29,928
Total expense (income) for the year			31,892
Foreign Plan [Member]
Components of net periodic benefit cost:
Service cost			824
Interest cost			1,735
Expected return on plan assets			(2,346)
Amortization of losses			221
Net periodic benefit cost			434
Curtailment/Settlement loss (gain)
Total expense (income) for the year			$ 434