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REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended
REVENUE (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 262,390	$ 181,035
Contract asset	5,400		$ 4,800
Contract liability	600		$ 400
Revenue recognized from prior period	300
Estimated variable consideration, increase in revenue	900
Mortgage products
Disaggregation of Revenue [Line Items]
Revenue	45,984	73,462
Credit Cards
Disaggregation of Revenue [Line Items]
Revenue	54,506	46,132
Personal Loans
Disaggregation of Revenue [Line Items]
Revenue	32,531	25,965
Insurance
Disaggregation of Revenue [Line Items]
Revenue	67,092	13
Other Products And Services
Disaggregation of Revenue [Line Items]
Revenue	62,277	35,463
Non-mortgage products
Disaggregation of Revenue [Line Items]
Revenue	$ 216,406	$ 107,573