Note 1 - Summary of Significant Accounting Policies - Changes in Carrying Amounts of Goodwill (Details) - USD ($)	12 Months Ended
Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Balance	$ 61,218,000
Acquisitions	0
Impairment	0	$ 0	$ 0
Foreign currency translation	7,536,000
Balance	$ 68,754,000	$ 61,218,000

The amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

No definition available.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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-Name Accounting Standards Codification
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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