Note 5 - Goodwill and Intangible Assets (Details) - Goodwill (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Balance	$ 369,312us-gaap_Goodwill	$ 370,143us-gaap_Goodwill
Goodwill acquired during the year	136,034us-gaap_GoodwillAcquiredDuringPeriod	3,024us-gaap_GoodwillAcquiredDuringPeriod
Adjustments to prior year acquisitions	(260)	5,607
Effect of foreign currency translation	(9,407)us-gaap_GoodwillTranslationAdjustments	(9,462)us-gaap_GoodwillTranslationAdjustments
Balance	495,679us-gaap_Goodwill	369,312us-gaap_Goodwill
UNITED STATES
Goodwill [Line Items]
Balance	273,070	266,521
Goodwill acquired during the year	128,426	350
Adjustments to prior year acquisitions	64	6,199
Balance	401,560	273,070
CANADA
Goodwill [Line Items]
Balance	19,279	21,041
Effect of foreign currency translation	(2,101)	(1,762)
Balance	17,178	19,279
UNITED KINGDOM
Goodwill [Line Items]
Balance	39,593	36,118
Goodwill acquired during the year	1,640	2,674
Adjustments to prior year acquisitions	(324)
Effect of foreign currency translation	(2,555)	801
Balance	38,354	39,593
AUSTRALIA
Goodwill [Line Items]
Balance	37,370	46,463
Goodwill acquired during the year	5,968
Adjustments to prior year acquisitions		(592)
Effect of foreign currency translation	(4,751)	(8,501)
Balance	$ 38,587	$ 37,370

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e961-128460

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