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REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
REVENUE (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jan. 01, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 197,057	$ 171,494	$ 562,193	$ 456,782
Contract asset	4,300		4,300		$ 1,900
Contract liability	300		300
Revenue recognized from prior period	100
Mortgage products
Disaggregation of Revenue [Line Items]
Revenue	55,287	73,756	195,697	208,209
Credit Cards
Disaggregation of Revenue [Line Items]
Revenue	42,698	39,369	127,577	110,134
Personal Loans
Disaggregation of Revenue [Line Items]
Revenue	38,569	25,449	100,744	62,984
Other Products And Services
Disaggregation of Revenue [Line Items]
Revenue	60,503	32,920	138,175	75,455
Non-mortgage products
Disaggregation of Revenue [Line Items]
Revenue	$ 141,770	$ 97,738	$ 366,496	$ 248,573