SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - CONCENTRATION (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Mortgage Banking Activities
Initial amortization period of MSRs	7 years
Impairment in MSR portfolio	$ 0	$ 0
Loan Servicing Income	$ 2,506	$ 2,418	$ 2,169
Warehouse lines of credit | Geographic concentration risk | California
Mortgage Banking Activities
Concentration Risk, Percentage	29.00%
Net income | Geographic concentration risk | Republic Processing Group
Mortgage Banking Activities
Concentration Risk, Percentage	25.00%	27.00%	25.00%
Net income | Geographic concentration risk | Tax Refund Solutions
Mortgage Banking Activities
Concentration Risk, Percentage	14.00%	14.00%	13.00%
Net income | Geographic concentration risk | Republic Credit Solutions
Mortgage Banking Activities
Concentration Risk, Percentage	11.00%	13.00%	12.00%
Net income | Geographic concentration risk | Warehouse Lending
Mortgage Banking Activities
Concentration Risk, Percentage	5.00%	5.00%	7.00%