Note 16 - Pension Plan - Changes in Plan Assets (Details) - Pension Plan [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Fair value of plan assets	$ 33,016	$ 30,627
Expected net return on plan assets	640	787
Employer	609	603
Plan participants	308	336
Benefits paid	(495)	(438)
Other costs	(72)	(168)
Foreign exchange	4,658	(916)
Expected fair value of plan assets - December 31	38,664	30,831
Actuarial gain, net of foreign exchange	149	2,185
Fair value of plan assets	$ 38,813	$ 33,016

Represents the actuarial gain on plan assets under defined benefit plan, net of foreign currency exchange.

No definition available.

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Represents the amount of expected fair value of plan assets under defined benefit plan.

+ References

No definition available.

+ Details

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- Definition

Amount of administration expense of defined benefit plan which decreases plan assets. Excludes plan administration expense paid by employer.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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
-Paragraph 1
-Subparagraph (d)(5)(ii)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(iv)(01)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

+ References

+ Details

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- Definition

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

+ Details

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Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 60
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(5)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Period Type:	duration

- Definition

Amount of contributions received by defined benefit plan from participant which increases plan assets.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ References

+ Details

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- Details

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