Note 3 - Acquisitions (Details) $ in Thousands	12 Months Ended
Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Note 3 - Acquisitions (Details) [Line Items]
Number of Businesses Acquired	9	9	8
Business Combination Gain on Revaluation of Previously Held Equity Investment			$ 820
Business Combination, Acquisition Related Costs	$ 5,301	$ 9,103	2,903
Business Acquisition, Goodwill, Expected Tax Deductible Amount	25,745	712
Business Combination, Contingent Consideration, Liability	$ 29,119
Americas [Member]
Note 3 - Acquisitions (Details) [Line Items]
Number of Businesses Acquired	7
EMEA [Member]
Note 3 - Acquisitions (Details) [Line Items]
Number of Businesses Acquired	2
Acquisitions After December 31, 2008 [Member]
Note 3 - Acquisitions (Details) [Line Items]
Business Combination, Contingent Consideration, Liability	$ 29,119
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, Low	43,794
Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High	48,660
Contingent Consideration Paid	$ 6,083	$ 25,535	$ 1,994

The business combination gain on revaluation of previously held equity investment.

No definition available.

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- Definition

The contingent consideration paid.

+ References

No definition available.

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

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- Definition

For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
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- Definition

For contingent consideration arrangements and indemnification assets recognized in connection with a business combination, this element represents an estimate of the low-end of the potential range (undiscounted) of the consideration which may be paid.

+ References

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-Publisher FASB
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- Definition

Amount of liability recognized arising from contingent consideration in a business combination.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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-Paragraph 6
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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

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