STOCK-BASED COMPENSATION (Details - P&L Impact) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Non-cash compensation expense related to equity awards
Total non-cash compensation	$ 15,982	$ 11,178	$ 30,035	$ 22,287
Cost of revenue
Non-cash compensation expense related to equity awards
Total non-cash compensation	197	79	350	137
Selling and marketing expense
Non-cash compensation expense related to equity awards
Total non-cash compensation	2,283	1,433	4,032	2,934
General and administrative expense
Non-cash compensation expense related to equity awards
Total non-cash compensation	11,686	8,490	21,907	17,229
Product development
Non-cash compensation expense related to equity awards
Total non-cash compensation	$ 1,816	$ 1,176	$ 3,746	$ 1,987