INVESTMENT SECURITIES - Investment Securities (Details) - Available-for-sale Securities - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2021	Dec. 31, 2020
Available-for-sale Securities, Amortized Cost Amount	$ 417,348	$ 384,807
Available-for-sale Securities, Gross Unrealized Gain	18,241	31,338
Available-for-sale Securities, Gross Unrealized Loss	2,651	1,212
Available-for-sale Securities, Fair Value	432,938	414,933
Agency mortgage-backed securities.
Available-for-sale Securities, Amortized Cost Amount	157,316	151,106
Available-for-sale Securities, Gross Unrealized Gain	12,402	19,665
Available-for-sale Securities, Gross Unrealized Loss	898	831
Available-for-sale Securities, Fair Value	168,820	169,940
Agency collateralized mortgage obligations
Available-for-sale Securities, Amortized Cost Amount	203,680	168,472
Available-for-sale Securities, Gross Unrealized Gain	3,688	8,524
Available-for-sale Securities, Gross Unrealized Loss	1,637	375
Available-for-sale Securities, Fair Value	205,731	176,621
States and political subdivisions securities
Available-for-sale Securities, Amortized Cost Amount	38,571	45,196
Available-for-sale Securities, Gross Unrealized Gain	1,582	2,135
Available-for-sale Securities, Gross Unrealized Loss	116	6
Available-for-sale Securities, Fair Value	40,037	47,325
Small Business Administration securities
Available-for-sale Securities, Amortized Cost Amount	17,781	20,033
Available-for-sale Securities, Gross Unrealized Gain	569	1,014
Available-for-sale Securities, Fair Value	$ 18,350	$ 21,047

Represents the monetary amount of Available for Sale Securities Fair Value, as of the indicated date.

No definition available.

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- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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- Definition

Amount of unrealized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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- Definition

Amount of unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27161-111563

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