Note 17 - Retirement Plans - Plan Assets and Funded Status of the Domestic Pension Plan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Fair value of plan assets, beginning of period	$ 39,524
Fair value of plan assets, end of period	46,650	$ 39,524
Pension Plan [Member] \| UNITED STATES
Fair value of plan assets, beginning of period	39,524	39,135
Actual return on plan assets	6,663	2,910
Contributions	3,885	1,134
Benefits paid	(3,422)	(3,655)
Fair value of plan assets, end of period	46,650	39,524
Unfunded status	(12,536)	(18,194)
Accrued benefit cost, end of period	$ (12,536)	$ (18,194)

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

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Amount of increase (decrease) in plan assets of defined benefit plan from actual return (loss) determined by change in fair value of plan assets adjusted for contributions, benefit payments, and other expenses.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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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.

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- Definition

Amount of accumulated benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of payment to participant under defined benefit plan which decreases plan assets. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

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