FAIR VALUE - Summary of Estimated Fair Values and Carrying Amounts of Financial Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Financial assets:
Cash and due from banks	$ 107,729	$ 77,693
Interest-bearing deposits with banks	769,099	39,501
Securities available for sale	450,360	638,291
Securities held to maturity	89,325	135,027
Loans held for sale	52,800	12,600
Accrued interest receivable	16,566	10,908
Financial liabilities:
Certificates of deposit	288,445
Carrying Amount
Financial assets:
Cash and due from banks	107,729	77,693
Interest-bearing deposits with banks	769,099	39,501
Securities available for sale	450,360	638,291
Securities restricted	23,362	32,879
Securities held to maturity	85,700	133,638
Loans held for sale	52,785	12,643
Loans, net	4,553,203	3,647,499
Derivatives	49,662	15,437
Accrued interest receivable	16,566	10,908
Financial liabilities:
Certificates of deposit	288,445	307,977
Demand and other deposits	5,200,808	3,506,670
FHLB advances	215,000	435,000
Repurchase agreements	1,223	999
Subordinated debentures	79,059	78,920
Derivatives	56,417	16,645
Accrued interest payable	881	1,467
Fair Value
Financial assets:
Cash and due from banks	107,729	77,693
Interest-bearing deposits with banks	769,099	39,501
Securities available for sale	450,360	638,291
Securities held to maturity	89,325	135,027
Loans held for sale	52,785	12,643
Loans, net	4,554,333	3,685,770
Derivatives	49,662	15,437
Accrued interest receivable	16,566	10,908
Financial liabilities:
Certificates of deposit	290,971	308,660
Demand and other deposits	5,200,808	3,506,670
FHLB advances	221,665	434,622
Repurchase agreements	1,223	999
Subordinated debentures	86,704	81,010
Derivatives	56,417	16,645
Accrued interest payable	881	1,467
Quoted Prices In Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and due from banks	107,729	77,693
Interest-bearing deposits with banks	769,099	39,501
Loans held for sale	42,785
Loans, net	0
Financial liabilities:
Demand and other deposits	5,200,808	3,506,670
FHLB advances		195,000
Significant Other Observable Inputs (Level 2)
Financial assets:
Securities available for sale	450,360	638,291
Securities held to maturity	89,325	135,027
Loans, net	0
Derivatives	49,662	15,437
Accrued interest receivable	1,421	2,181
Financial liabilities:
Certificates of deposit	290,971	308,660
FHLB advances	221,665	239,622
Repurchase agreements	1,223	999
Subordinated debentures	86,704	81,010
Derivatives	56,417	16,645
Accrued interest payable	881	1,467
Significant Unobservable Inputs (Level 3)
Financial assets:
Loans held for sale	10,000	12,643
Loans, net	4,554,333	3,685,770
Accrued interest receivable	$ 15,145	$ 8,727