Note 5 - Goodwill and Intangible Assets (Details) - Goodwill (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014
Goodwill [Line Items]
Balance	$ 369,312
Goodwill acquired during the year	68,201
Adjustments to prior year acquisitions	(309)
Effect of foreign currency translation	1,794
Balance	438,998
UNITED STATES
Goodwill [Line Items]
Balance	273,070
Goodwill acquired during the year	60,430
Adjustments to prior year acquisitions	64
Balance	333,564
CANADA
Goodwill [Line Items]
Balance	19,279
Effect of foreign currency translation	(939)
Balance	18,340
UNITED KINGDOM
Goodwill [Line Items]
Balance	39,593
Goodwill acquired during the year	1,588
Adjustments to prior year acquisitions	(373)
Effect of foreign currency translation	399
Balance	41,207
AUSTRALIA
Goodwill [Line Items]
Balance	37,370
Goodwill acquired during the year	6,183
Effect of foreign currency translation	2,334
Balance	$ 45,887