PARENT COMPANY AND REGULATORY RESTRICTIONS (Condensed Statements of Income) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Expense:
Interest on long-term debt									$ 3,602	$ 4,080	$ 4,556
Income tax expense	$ 3,772	$ 2,200	$ 2,967	$ 2,821	$ 5,165	$ 4,895	$ 4,427	$ 5,118	11,760	19,605	18,758
Net income	$ 12,171	$ 6,859	$ 9,917	$ 8,326	$ 14,197	$ 14,554	$ 13,534	$ 16,037	37,273	58,322	59,486
Parent
Income:
Dividends from subsidiary bank									24,015	42,008	103,001
Interest income:
Interest income from subsidiary bank									4	5	5
Other income									52	92	160
Total income									24,071	42,105	103,166
Expense:
Interest on long-term debt									2,095	2,453	4,338
Other expenses									1,293	2,599	1,617
Total expenses									3,388	5,052	5,955
Income before income taxes and equity in undistributed income of subsidiaries									20,683	37,053	97,211
Income tax expense									(690)	(1,289)	(1,261)
Income before equity in undistributed income of subsidiaries									21,373	38,342	98,472
Equity in undistributed income (loss) of subsidiary bank									15,900	19,980	(38,986)
Net income									$ 37,273	$ 58,322	$ 59,486