INVESTMENT SECURITIES - Investment Securities (Details) - Available-for-sale Securities - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2021	Dec. 31, 2020
Available-for-sale Securities, Amortized Cost Amount	$ 445,566	$ 384,807
Available-for-sale Securities, Gross Unrealized Gain	17,327	31,338
Available-for-sale Securities, Gross Unrealized Loss	5,225	1,212
Available-for-sale Securities, Fair Value	457,668	414,933
Agency mortgage-backed securities
Available-for-sale Securities, Amortized Cost Amount	159,967	151,106
Available-for-sale Securities, Gross Unrealized Gain	11,283	19,665
Available-for-sale Securities, Gross Unrealized Loss	1,482	831
Available-for-sale Securities, Fair Value	169,768	169,940
Agency collateralized mortgage obligations
Available-for-sale Securities, Amortized Cost Amount	226,494	168,472
Available-for-sale Securities, Gross Unrealized Gain	4,182	8,524
Available-for-sale Securities, Gross Unrealized Loss	3,594	375
Available-for-sale Securities, Fair Value	227,082	176,621
States and political subdivisions securities
Available-for-sale Securities, Amortized Cost Amount	39,833	45,196
Available-for-sale Securities, Gross Unrealized Gain	1,546	2,135
Available-for-sale Securities, Gross Unrealized Loss	149	6
Available-for-sale Securities, Fair Value	41,230	47,325
Small Business Administration securities
Available-for-sale Securities, Amortized Cost Amount	19,272	20,033
Available-for-sale Securities, Gross Unrealized Gain	316	1,014
Available-for-sale Securities, Fair Value	$ 19,588	$ 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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Data Type:	xbrli:monetaryItemType
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- Definition

This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ 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=121645371&loc=d3e27161-111563

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

+ 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=121645371&loc=d3e27161-111563

+ Details

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