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REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
REVENUE (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Jan. 01, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 184,101	$ 152,773	$ 365,136	$ 285,288
Contract asset	2,800		2,800		$ 1,900
Contract liability	100		100
Revenue recognized from prior period	200
Mortgage products
Disaggregation of Revenue [Line Items]
Revenue	66,948	71,515	140,410	134,453
Credit Cards
Disaggregation of Revenue [Line Items]
Revenue	38,747	36,992	84,879	70,765
Personal Loans
Disaggregation of Revenue [Line Items]
Revenue	36,210	20,521	62,175	37,535
Other Products And Services
Disaggregation of Revenue [Line Items]
Revenue	42,196	23,745	77,672	42,535
Non-mortgage products
Disaggregation of Revenue [Line Items]
Revenue	$ 117,153	$ 81,258	$ 224,726	$ 150,835