Note 11 - Segment and Geographic Information (Detail) - Financial Information by Geographic Area (USD $) In Thousands, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2012		Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011		Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Revenues:
Revenues	$ 274,683		$ 265,155	$ 257,531	$ 230,594	$ 256,795		$ 246,218	$ 224,985	$ 210,587	$ 1,027,963		$ 938,585		$ 914,975
Operating income (loss)
Operating income (loss)	23,718		26,142	18,363	10,899	21,710		9,498	7,840	5,489	79,122		44,537		87,035
Long-lived assets: (1)
Long-lived assets	213,305	[1]				194,652	[1]				213,305	[1]	194,652	[1]	181,732	[1]
United States [Member]
Revenues:
Revenues											600,159		552,197		604,372
Operating income (loss)
Operating income (loss)											37,995		(2,212)		40,172
Long-lived assets: (1)
Long-lived assets	154,145	[1]				146,487	[1]				154,145	[1]	146,487	[1]	147,572	[1]
Canada [Member]
Revenues:
Revenues											180,283		178,739		139,632
Operating income (loss)
Operating income (loss)											31,376		31,892		30,958
Long-lived assets: (1)
Long-lived assets	28,724	[1]				22,998	[1]				28,724	[1]	22,998	[1]	20,564	[1]
Europe [Member]
Revenues:
Revenues											86,883		102,471		87,616
Operating income (loss)
Operating income (loss)											6,196		9,391		9,041
Long-lived assets: (1)
Long-lived assets	16,396	[1]				12,474	[1]				16,396	[1]	12,474	[1]	13,596	[1]
Other Foreign [Member]
Revenues:
Revenues											160,638		105,178		83,355
Operating income (loss)
Operating income (loss)											3,555		5,466		6,864
Long-lived assets: (1)
Long-lived assets	$ 14,040	[1]				$ 12,693	[1]				$ 14,040	[1]	$ 12,693	[1]		[1]

[1] Long lived assets as of December 31, 2012, 2011 and 2010 do not include intangible assets, goodwill or deferred tax assets.