Note 5 - Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Customer Relationships [Member] \| Minimum [Member]
Estimated useful lives	3 years 120 days	3 years 120 days
Customer Relationships [Member] \| Maximum [Member]
Estimated useful lives	5 years	5 years
Customer Relationships [Member]
Gross carrying amount	$ 296,657	$ 263,293
Accumulated amortization	(212,493)	(199,266)
Net carrying value	$ 84,164	$ 64,027
Trade Names [Member] \| Minimum [Member]
Estimated useful lives	3 years 270 days	3 years 270 days
Trade Names [Member] \| Maximum [Member]
Estimated useful lives	7 years	7 years
Trade Names [Member]
Gross carrying amount	$ 75,323	$ 68,172
Accumulated amortization	(54,651)	(52,354)
Net carrying value	$ 20,672	$ 15,818
Noncompete Agreements [Member]
Estimated useful lives	3 years	3 years
Gross carrying amount	$ 10,729	$ 10,254
Accumulated amortization	(6,605)	(6,047)
Net carrying value	$ 4,124	$ 4,207
Unpatented Technology [Member] \| Minimum [Member]
Estimated useful lives	2 years	2 years
Unpatented Technology [Member] \| Maximum [Member]
Estimated useful lives	3 years 120 days	3 years 120 days
Unpatented Technology [Member]
Gross carrying amount	$ 8,973	$ 9,014
Accumulated amortization	(8,524)	(8,393)
Net carrying value	449	621
Gross carrying amount	391,682	350,733
Accumulated amortization	(282,273)	(266,060)
Net carrying value	$ 109,409	$ 84,673

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

Name:	us-gaap_FiniteLivedIntangibleAssetUsefulLife
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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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Namespace Prefix:
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Balance Type:
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_TradeNamesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_NoncompeteAgreementsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis=us-gaap_UnpatentedTechnologyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: