Segment and Geographic Information (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Geographic Information regarding revenues
Total revenues	$ 440,317	$ 379,935	$ 1,284,816	$ 1,109,516
United States [Member]
Geographic Information regarding revenues
Total revenues	218,074	100,032	582,177	288,169
United Kingdom [Member]
Geographic Information regarding revenues
Total revenues	131,861	154,892	409,231	474,249
Asia [Member]
Geographic Information regarding revenues
Total revenues	51,368	63,769	160,175	182,276
France [Member]
Geographic Information regarding revenues
Total revenues	22,360	34,080	73,613	97,356
Other Americas [Member]
Geographic Information regarding revenues
Total revenues	9,684	11,671	32,391	34,635
Other Europe/MEA [Member]
Geographic Information regarding revenues
Total revenues	$ 6,970	$ 15,491	$ 27,229	$ 32,831