Note 6 - Employee Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Oct. 01, 2017	Oct. 02, 2016	Oct. 01, 2017	Oct. 02, 2016
Pension Plan [Member] \| Foreign Plan [Member]
Service cost	$ 423	$ 260	$ 1,204	$ 781
Interest cost	1,426	1,610	4,138	5,058
Expected return on assets	(1,697)	(1,876)	(4,920)	(5,880)
Amortization of prior service costs	9	9	26	27
Recognized net actuarial losses	318	169	930	537
Net periodic benefit cost	479	172	1,378	523
Salary Continuation Plan [Member] \| Domestic Plan [Member]
Service cost	0	110	0	330
Interest cost	314	317	942	952
Recognized net actuarial losses	91	203	273	608
Net periodic benefit cost	$ 405	$ 630	$ 1,215	$ 1,890

Amount of prior service cost (credit) recognized in net periodic benefit cost (credit) of defined benefit plan.

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- Definition

Amount, before tax, after reclassification adjustment, of increase (decrease) in accumulated other comprehensive income from gain (loss) of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

+ Details

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- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

+ References

+ Details

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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

+ References

+ Details

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

+ Details

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- Definition

Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

+ Details

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- Details

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- Details

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