SEGMENT INFORMATION (Details) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2017 USD ($) segment	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
SEGMENT INFORMATION
Number of reportable segments | segment									1
Revenue	$ 160,954	$ 171,494	$ 152,773	$ 132,515	$ 100,841	$ 94,558	$ 94,290	$ 94,713	$ 617,736	$ 384,402	$ 254,216
Mortgage Products [Member]
SEGMENT INFORMATION
Revenue									275,910	219,991	165,272
Non-mortgage Products [Member]
SEGMENT INFORMATION
Revenue									$ 341,826	$ 164,411	$ 88,944