Note 4 - Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2017	Dec. 31, 2016
Gross value	$ 197,499	$ 121,259
Accumulated amortization	(99,409)	(83,462)
Net carrying amount	98,090	37,797
Customer Relationships [Member]
Gross value	159,290	103,090
Accumulated amortization	(84,106)	(71,914)
Net carrying amount	$ 75,184	$ 31,176
Customer Relationships [Member] \| Minimum [Member]
Useful life (Year)	5 years	5 years
Customer Relationships [Member] \| Maximum [Member]
Useful life (Year)	15 years	10 years
Trade Names [Member]
Gross value	$ 16,246	$ 15,936
Accumulated amortization	(13,263)	(11,393)
Net carrying amount	$ 2,983	$ 4,543
Trade Names [Member] \| Minimum [Member]
Useful life (Year)	1 year 182 days	3 years
Trade Names [Member] \| Maximum [Member]
Useful life (Year)	5 years	5 years
Intellectual Property [Member]
Gross value	$ 21,700	$ 2,100
Accumulated amortization	(1,952)	(140)
Net carrying amount	$ 19,748	$ 1,960
Intellectual Property [Member] \| Minimum [Member]
Useful life (Year)	3 years	3 years
Intellectual Property [Member] \| Maximum [Member]
Useful life (Year)	7 years	7 years
Restrictive Covenant [Member]
Gross value	$ 263	$ 133
Accumulated amortization	(88)	(15)
Net carrying amount	$ 175	$ 118
Restrictive Covenant [Member] \| Minimum [Member]
Useful life (Year)	1 year	3 years
Restrictive Covenant [Member] \| Maximum [Member]
Useful life (Year)	5 years	5 years

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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