RELATED PARTY TRANSACTIONS (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) directors	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Related Party Transactions [Abstract]
Number Of Board Of Directors Also Serving As Director To Marketing Partner Of The Company | directors		1
Expenses incurred for related parties		$ 700	$ 1,200	$ 1,300
Charitable Contribution, Total	$ 10,000	10,000
Contribution to LendingTree Foundation, Current	$ 10,000	$ 3,333	$ 10,000