INVESTMENT SECURITIES, Analysis of Gross Unrealized Losses (Details)	Sep. 30, 2021 USD ($) Security	Dec. 31, 2020 USD ($)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	$ 371,231,000	$ 95,948,000
12 months or more, fair value	4,368,000	0
Total fair value	375,599,000	95,948,000
Less than 12 months, unrealized losses	(3,435,000)	(374,000)
12 Months or more, unrealized losses	(133,000)	0
Total unrealized losses	$ (3,568,000)	(374,000)
Investment securities in an unrealized loss position less than 12 months | Security	152
Investment securities in an unrealized loss position more than 12 months | Security	3
Investment securities pledged as collateral	$ 41,004,000	41,916,000
U.S. Treasury Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	51,178,000	4,276,000
12 months or more, fair value	0	0
Total fair value	51,178,000	4,276,000
Less than 12 months, unrealized losses	(187,000)	(1,000)
12 Months or more, unrealized losses	0	0
Total unrealized losses	(187,000)	(1,000)
Securities of U.S. Government Agencies and Corporations [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	68,390,000	58,164,000
12 months or more, fair value	3,459,000	0
Total fair value	71,849,000	58,164,000
Less than 12 months, unrealized losses	(924,000)	(265,000)
12 Months or more, unrealized losses	(41,000)	0
Total unrealized losses	(965,000)	(265,000)
Obligations of States and Political Subdivisions [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	13,830,000	1,603,000
12 months or more, fair value	909,000	0
Total fair value	14,739,000	1,603,000
Less than 12 months, unrealized losses	(268,000)	(9,000)
12 Months or more, unrealized losses	(92,000)	0
Total unrealized losses	(360,000)	(9,000)
Collateralized Mortgage Obligations [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	85,401,000	1,697,000
12 months or more, fair value	0	0
Total fair value	85,401,000	1,697,000
Less than 12 months, unrealized losses	(650,000)	(8,000)
12 Months or more, unrealized losses	0	0
Total unrealized losses	(650,000)	(8,000)
Mortgage-backed Securities [Member]
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, fair value	152,432,000	30,208,000
12 months or more, fair value	0	0
Total fair value	152,432,000	30,208,000
Less than 12 months, unrealized losses	(1,406,000)	(91,000)
12 Months or more, unrealized losses	0	0
Total unrealized losses	$ (1,406,000)	$ (91,000)