INVESTMENT SECURITIES - Schedule of Gross Unrealized Losses and Fair Value of Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Estimated Fair Value
Less than 12 months, estimated fair value	$ 30,050	$ 131,176
12 months or more, estimated fair value	6,465	57,151
Total estimated fair value	36,515	188,327
Unrealized Losses
Less than 12 months, unrealized losses	(252)	(705)
12 months or more, unrealized losses	(174)	(591)
Total unrealized losses	(426)	(1,296)
State, county and municipal securities
Estimated Fair Value
Less than 12 months, estimated fair value	548	803
12 months or more, estimated fair value	0	0
Total estimated fair value	548	803
Unrealized Losses
Less than 12 months, unrealized losses	0	(2)
12 months or more, unrealized losses	0	0
Total unrealized losses	0	(2)
Corporate debt securities
Estimated Fair Value
Less than 12 months, estimated fair value	13,438	2,573
12 months or more, estimated fair value	0	0
Total estimated fair value	13,438	2,573
Unrealized Losses
Less than 12 months, unrealized losses	(127)	(2)
12 months or more, unrealized losses	0	0
Total unrealized losses	(127)	(2)
SBA pool securities
Estimated Fair Value
Less than 12 months, estimated fair value	3,814	28,521
12 months or more, estimated fair value	4,168	4,825
Total estimated fair value	7,982	33,346
Unrealized Losses
Less than 12 months, unrealized losses	(13)	(285)
12 months or more, unrealized losses	(105)	(124)
Total unrealized losses	(118)	(409)
Mortgage-backed securities
Estimated Fair Value
Less than 12 months, estimated fair value	12,250	99,279
12 months or more, estimated fair value	2,297	52,326
Total estimated fair value	14,547	151,605
Unrealized Losses
Less than 12 months, unrealized losses	(112)	(416)
12 months or more, unrealized losses	(69)	(467)
Total unrealized losses	$ (181)	$ (883)