Note 13 - Geographic Information (Detail) - Revenues 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	$ 211,079	$ 204,388	$ 197,481	$ 198,533	$ 185,885	$ 179,356	$ 168,392	$ 167,999	$ 811,481	$ 701,632	$ 620,385
United States [Member]
Revenues:
Revenues									303,213	206,110	183,408
United Kingdom [Member]
Revenues:
Revenues									69,804	66,055	57,852
Not Connected to a Country [Member]
Revenues:
Revenues									404,596	395,743	345,349
Other Countries [Member]
Revenues:
Revenues									$ 33,868	$ 33,724	$ 33,776