Note 14 - Retirement and Pension Plans - Actuarial Assumptions to Determine the Net Periodic Benefit Cost (Details)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Discount rate	1.50%	2.00%	2.00%
Rate of compensation increases	2.00%	2.00%	2.00%
Expected long-term rate of return on plan assets	1.80%	1.80%	1.80%

The interest rate used to adjust for the time value of money.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Expected Long-Term Rate of Return on Plan Assets
-URI http://asc.fasb.org/extlink&oid=6512046

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(3)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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- Definition

Expected rate of compensation increases (for pay-related plans).

+ 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 (k)(2)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

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