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LOANS - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Loans held for sale
Total LHFS	$ 6,703		$ 7,678
Loans held for investment
Loans held for investment	3,124,924		2,959,553
Less allowance for credit losses	(32,400)	$ (31,620)	(30,742)	$ (32,457)	$ (32,663)	$ (35,820)
Net LHFI	3,092,524		2,928,811
Mortgage loans held for sale
Loans held for sale
Total LHFS	6,703		7,678
Commercial, financial and agriculture
Loans held for investment
Loans held for investment	402,619		397,516
Less allowance for credit losses	(4,511)	(4,874)	(4,873)	(3,910)	(4,158)	(6,214)
Commercial real estate
Loans held for investment
Loans held for investment	1,810,204		1,683,698
Less allowance for credit losses	(18,668)	(17,773)	(17,552)	(17,573)	(17,578)	(24,319)
Consumer real estate
Loans held for investment
Loans held for investment	871,051		838,654
Less allowance for credit losses	(8,752)	(8,492)	(7,889)	(10,339)	(10,280)	(4,736)
Consumer installment
Loans held for investment
Loans held for investment	41,050		39,685
Less allowance for credit losses	$ (469)	$ (481)	$ (428)	$ (635)	$ (647)	$ (551)