LOAN SERVICING RIGHTS - Schedule of Activity of Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance			$ 136,542
Ending balance	$ 197,798		197,798
Residential mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	154,746	$ 85,922	130,630	$ 94,902
Additions	43,377	19,298	65,244	35,359
Amortization	(7,197)	(5,687)	(14,681)	(9,853)
Recoveries/(impairment)	749	(8,152)	10,482	(29,027)
Ending balance	191,675	91,381	191,675	91,381
Residential mortgage servicing valuation allowance
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	29,674	20,979	39,407	104
Additions	0	8,152	0	29,027
Recoveries/(impairment)	(749)	0	(10,482)	0
Ending balance	28,925	29,131	28,925	29,131
SBA servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	6,445	5,394	5,839	7,886
Additions	241	100	471	475
Purchase accounting adjustment	0	0	0	(1,214)
Amortization	(563)	(416)	(1,092)	(779)
Recoveries/(impairment)	0	163	905	(1,127)
Ending balance	6,123	5,241	6,123	5,241
SBA servicing valuation allowance
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	0	1,431	905	141
Additions	0	0	0	1,127
Recoveries/(impairment)	0	(163)	(905)	0
Ending balance	0	1,268	0	1,268
Indirect automobile
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	29	204	73	247
Amortization	(29)	(42)	(73)	(85)
Ending balance	$ 0	$ 162	$ 0	$ 162