Note 18 - Retirement Plans - Plan Assets and Funded Status of the Domestic Pension Plan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Fair value of plan assets, beginning of period	$ 39,135
Fair value of plan assets, end of period	39,524	$ 39,135
United States Pension Plan of US Entity [Member]
Fair value of plan assets, beginning of period	39,135	41,665
Actual return on plan assets	2,910	(806)
Contributions	1,134	1,712
Benefits paid	(3,655)	(3,436)
Fair value of plan assets, end of period	39,524	39,135
Unfunded status	(18,194)	(19,421)
Accrued benefit cost, end of period	$ (18,194)	$ (19,421)

Represents the amount of accrued benefit cost related to defined benefit plan.

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The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Actual Return on Plan Assets (Component of Net Periodic Postretirement Benefit Cost)
-URI http://asc.fasb.org/extlink&oid=6504192

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-Publisher FASB
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The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of contributions made by the employer to defined benefit plans.

+ References

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Fair value of assets that have been segregated and restricted to provide pension or postretirement benefits. Assets include, but are not limited to, stocks, bonds, other investments, earnings from investments, and contributions by the employer and employees.

+ References

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- Definition

If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented.

+ References

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