STOCK-BASED COMPENSATION - Schedule of Non-cash Compensation Related to Equity Awards (Details ) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash compensation	$ 15,575	$ 17,074	$ 47,990	$ 51,804
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash compensation	417	371	1,252	1,231
Selling and marketing expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash compensation	2,198	1,805	6,522	5,583
General and administrative expense
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash compensation	11,212	13,233	32,685	38,658
Product development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash compensation	1,748	1,665	6,448	6,332
Restructuring and severance
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash compensation	$ 0	$ 0	$ 1,083	$ 0