Note 10 - Accumulated Other Comprehensive Loss - Components of Accumulated Other Comprehensive Loss, Net of Tax (Details) - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Accumulated net currency translation adjustments	$ (13,771)	$ (25,116)
Accumulated net adjustments related to postretirement benefits	(4,009)	(2,761)
Accumulated net unrealized gain/loss on investments	(7)	(5)
Total accumulated other comprehensive loss	$ (17,787)	$ (27,882)

Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Subparagraph (a)
-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
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-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
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-URI http://asc.fasb.org/extlink&oid=64808268&loc=d3e32022-110900

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580

Reference 6: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 830
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901

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