Note 5 - Goodwill and Intangible Assets (Details) - Goodwill (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015
Goodwill [Line Items]
Balance	$ 495,679	[1]
Goodwill acquired during the year	807	[1]
Adjustments to prior year acquisitions	468	[1]
Effect of foreign currency translation	(6,947)	[1]
Balance	490,007	[1]
UNITED STATES
Goodwill [Line Items]
Balance	401,560	[1]
Goodwill acquired during the year	807	[1]
Adjustments to prior year acquisitions	468	[1]
Effect of foreign currency translation		[1]
Balance	402,835	[1]
CANADA
Goodwill [Line Items]
Balance	17,178	[1]
Goodwill acquired during the year		[1]
Adjustments to prior year acquisitions		[1]
Effect of foreign currency translation	(2,021)	[1]
Balance	15,157	[1]
UNITED KINGDOM
Goodwill [Line Items]
Balance	38,354	[1]
Goodwill acquired during the year		[1]
Adjustments to prior year acquisitions		[1]
Effect of foreign currency translation	(1,868)	[1]
Balance	36,486	[1]
AUSTRALIA
Goodwill [Line Items]
Balance	38,587	[1]
Goodwill acquired during the year		[1]
Adjustments to prior year acquisitions		[1]
Effect of foreign currency translation	(3,058)	[1]
Balance	$ 35,529	[1]

[1] Goodwill recorded in connection with certain tax benefits to be realized in the Company's U.S. income tax returns has been reflected in the United States segment.