Note 5 - Goodwill and Intangible Assets (Details) - Goodwill (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Goodwill [Line Items]
Balance	$ 369,312
Goodwill acquired during the year	135,830
Adjustments to prior year acquisitions	(309)
Effect of foreign currency translation	5,051
Balance	509,884
UNITED STATES
Goodwill [Line Items]
Balance	273,070
Goodwill acquired during the year	125,764
Adjustments to prior year acquisitions	64
Balance	398,898
CANADA
Goodwill [Line Items]
Balance	19,279
Effect of foreign currency translation	(78)
Balance	19,201
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	1,478
Balance	42,286
AUSTRALIA
Goodwill [Line Items]
Balance	37,370
Goodwill acquired during the year	8,478
Effect of foreign currency translation	3,651
Balance	$ 49,499