Segments (Details) (USD $)	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Financial performance of the Company's reporting segments
Net revenues	$ 81,628,144	$ 55,951,378	$ 212,465,972	$ 154,399,483
Direct costs	(40,975,055)	(32,386,212)	(110,767,715)	(85,075,057)
Direct contribution	40,653,089	23,565,166	101,698,257	69,324,426
Operating expenses and indirect costs of net revenues	(10,689,366)	(4,254,460)	(30,891,982)	(15,694,887)
Income from operations	29,963,723	19,310,706	70,806,275	53,629,539
Other income (expenses):
Interest income and other financial gains	2,913,596	1,361,899	7,037,264	3,073,427
Interest expense and other financial results	(1,052,865)	(567,969)	(2,562,633)	(6,919,307)
Foreign currency gain	3,284,190	(354,219)	2,080,822	7,275
Other income / (loss), net	(7,292)		253,148
Net income before income / asset tax expense	35,101,352	19,750,417	77,614,876	49,790,934
Brazil [Member]
Financial performance of the Company's reporting segments
Net revenues	46,003,915	31,077,654	120,659,242	88,210,536
Direct costs	(25,709,957)	(19,235,066)	(69,712,512)	(50,090,123)
Direct contribution	20,293,958	11,842,588	50,946,730	38,120,413
Argentina [Member]
Financial performance of the Company's reporting segments
Net revenues	15,828,272	10,802,682	38,800,077	28,609,190
Direct costs	(6,264,769)	(5,353,452)	(15,845,674)	(13,985,689)
Direct contribution	9,563,503	5,449,230	22,954,403	14,623,501
Mexico [Member]
Financial performance of the Company's reporting segments
Net revenues	5,608,572	4,722,635	16,212,999	13,861,921
Direct costs	(3,183,432)	(2,914,273)	(8,881,811)	(8,544,912)
Direct contribution	2,425,140	1,808,362	7,331,188	5,317,009
Venezuela [Member]
Financial performance of the Company's reporting segments
Net revenues	9,045,783	5,762,290	23,051,176	13,705,926
Direct costs	(3,180,061)	(2,653,357)	(9,096,997)	(6,759,831)
Direct contribution	5,865,722	3,108,933	13,954,179	6,946,095
Other Countries [Member]
Financial performance of the Company's reporting segments
Net revenues	5,141,602	3,586,117	13,742,478	10,011,910
Direct costs	(2,636,836)	(2,230,064)	(7,230,721)	(5,694,502)
Direct contribution	$ 2,504,766	$ 1,356,053	$ 6,511,757	$ 4,317,408

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