GEOGRAPHIC INFORMATION (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Geographic Information
Revenues	$ 990,770	$ 1,452,804	$ 1,102,716	$ 809,320	$ 731,316	$ 1,001,757	$ 767,439	$ 584,394	$ 4,355,610	$ 3,084,905	$ 2,338,212
Intangible assets, net	200,151				232,030				200,151	232,030	172,080
Goodwill	504,784				510,894				504,784	510,894	350,630
Other long-lived assets	198,892				205,565				198,892	205,565	288,573
United States
Geographic Information
Revenues									1,761,065	1,640,673	1,486,185
Intangible assets, net	1,776				3,460				1,776	3,460	4,590
Goodwill	37,306				37,306				37,306	37,306	35,806
Other long-lived assets	148,150				180,623				148,150	180,623	270,005
The Netherlands
Geographic Information
Revenues									1,638,851	916,617	558,410
Intangible assets, net	78,850				91,295				78,850	91,295	109,605
Goodwill	142,576				147,214				142,576	147,214	157,605
Other long-lived assets	22,716				7,401				22,716	7,401	6,923
United Kingdom
Geographic Information
Revenues									709,393	419,709	255,192
Intangible assets, net	117,906				135,041				117,906	135,041	54,743
Goodwill	248,789				250,261				248,789	250,261	141,226
Other long-lived assets	15,939				9,584				15,939	9,584	6,968
Other.
Geographic Information
Revenues									246,301	107,906	38,425
Intangible assets, net	1,619				2,234				1,619	2,234	3,142
Goodwill	76,113				76,113				76,113	76,113	15,993
Other long-lived assets	$ 12,087				$ 7,957				$ 12,087	$ 7,957	$ 4,677