EARNINGS PER SHARE AND STOCK-BASED COMPENSATION (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Non-cash compensation expense related to equity awards
Non-cash compensation expense	$ 1,309	$ 824	$ 3,565	$ 2,731
Cost of revenue
Non-cash compensation expense related to equity awards
Non-cash compensation expense	2	(1)	6	3
Selling and marketing expense
Non-cash compensation expense related to equity awards
Non-cash compensation expense	145	50	504	314
General and administrative expense
Non-cash compensation expense related to equity awards
Non-cash compensation expense	1,026	712	2,662	2,196
Product development
Non-cash compensation expense related to equity awards
Non-cash compensation expense	$ 136	$ 63	$ 393	$ 218