INVESTMENT SECURITIES - Schedule of Gross Unrealized Losses and Fair Value of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Estimated Fair Value
Less than 12 months, estimated fair value	$ 34,593	$ 131,176
12 months or more, estimated fair value	4,278	57,151
Total estimated fair value	38,871	188,327
Unrealized Losses
Less than 12 months, unrealized losses	(374)	(705)
12 months or more, unrealized losses	(107)	(591)
Total unrealized losses	(481)	(1,296)
State, county and municipal securities
Estimated Fair Value
Less than 12 months, estimated fair value		803
12 months or more, estimated fair value		0
Total estimated fair value		803
Unrealized Losses
Less than 12 months, unrealized losses		(2)
12 months or more, unrealized losses		0
Total unrealized losses		(2)
Corporate debt securities
Estimated Fair Value
Less than 12 months, estimated fair value	9,906	2,573
12 months or more, estimated fair value	0	0
Total estimated fair value	9,906	2,573
Unrealized Losses
Less than 12 months, unrealized losses	(276)	(2)
12 months or more, unrealized losses	0	0
Total unrealized losses	(276)	(2)
SBA pool securities
Estimated Fair Value
Less than 12 months, estimated fair value	0	28,521
12 months or more, estimated fair value	4,276	4,825
Total estimated fair value	4,276	33,346
Unrealized Losses
Less than 12 months, unrealized losses	0	(285)
12 months or more, unrealized losses	(107)	(124)
Total unrealized losses	(107)	(409)
Mortgage-backed securities
Estimated Fair Value
Less than 12 months, estimated fair value	24,687	99,279
12 months or more, estimated fair value	2	52,326
Total estimated fair value	24,689	151,605
Unrealized Losses
Less than 12 months, unrealized losses	(98)	(416)
12 months or more, unrealized losses	0	(467)
Total unrealized losses	$ (98)	$ (883)