RELATED PARTY TRANSACTIONS WITH IAC - Narrative (Details) - USD ($) shares in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Related Party Transaction [Line Items]
Refunds received				$ 3,071,000
Distribution to IAC pursuant to the tax sharing agreement					$ 11,355,000
IAC | Services Agreement
Related Party Transaction [Line Items]
Charges for services rendered pursuant to the services agreement	$ 1,300,000	$ 1,000,000.0		3,600,000	3,700,000
Outstanding receivable due	0			0		$ 0
Outstanding payables due	0			0		0
IAC | Sublease Agreement
Related Party Transaction [Line Items]
Outstanding receivable due	100,000	100,000		100,000	100,000
Revenue from related parties	500,000	$ 500,000		1,400,000	$ 1,000,000.0
IAC | Tax Sharing Agreement
Related Party Transaction [Line Items]
Outstanding payables due	600,000			600,000		$ 200,000
Refunds received				$ 3,100,000
Distribution to IAC pursuant to the tax sharing agreement	$ 0		$ 11,400,000
IAC | Employee Matters Agreement
Related Party Transaction [Line Items]
Shares received from related party pursuant to employee matters agreement (shares)	0.1	0.1		0.3	0.5