LOAN SERVICING RIGHTS - Schedule of Activity of Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance			$ 103,035
Ending balance	$ 96,784		96,784
Residential mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	85,922	$ 12,104	94,902	$ 11,814
Additions	19,298	1,007	35,359	1,699
Amortization	(5,687)	(466)	(9,853)	(868)
(Impairment)/recovery	(8,152)	(1,460)	(29,027)	(1,460)
Ending balance	91,381	11,185	91,381	11,185
Residential mortgage servicing impairment
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	20,979	0	104	0
Additions	8,152	1,460	29,027	1,460
Ending balance	29,131	1,460	29,131	1,460
SBA servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	5,394	3,042	7,886	3,012
Additions	100	170	475	429
Purchase accounting adjustment	0	0	(1,214)	0
Amortization	(416)	(102)	(779)	(331)
(Impairment)/recovery	163	0	(1,127)	0
Ending balance	5,241	3,110	5,241	3,110
SBA servicing impairment
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	1,431	0	141	0
Additions	0	0	1,127	0
(Impairment)/recovery	163	0	0	0
Ending balance	1,268	0	1,268	0
Indirect automobile
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	204	0	247	0
Amortization	(42)	0	(85)	0
Ending balance	$ 162	$ 0	$ 162	$ 0