INVESTMENT SECURITIES - Amortized Cost and Fair Values of Investment Securities Available-for-sale (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	$ 421,272	$ 400,718
Unrealized Gain	4,833	10,440
Unrealized Loss	(4,639)	(534)
Investment securities available-for-sale	421,466	410,624
Total debt securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	420,394	399,790
Unrealized Gain	4,833	10,440
Unrealized Loss	(4,639)	(534)
Investment securities available-for-sale	420,588	409,696
United States government agency securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	41,105	53,207
Unrealized Gain	228	872
Unrealized Loss	(896)	(210)
Investment securities available-for-sale	40,437	53,869
United States sponsored mortgage-backed securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	77,519	94,968
Unrealized Gain	222	972
Unrealized Loss	(1,633)	(171)
Investment securities available-for-sale	76,108	95,769
United States treasury securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	112,133	3,000
Unrealized Gain	0	123
Unrealized Loss	(1,744)	0
Investment securities available-for-sale	110,389	3,123
Municipal securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	171,044	223,642
Unrealized Gain	4,334	8,327
Unrealized Loss	(366)	(82)
Investment securities available-for-sale	175,012	231,887
Corporate debt securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	11,093	17,473
Unrealized Gain	49	146
Unrealized Loss	0	(71)
Investment securities available-for-sale	11,142	17,548
Other debt securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	7,500	7,500
Unrealized Gain	0	0
Unrealized Loss	0	0
Investment securities available-for-sale	7,500	7,500
Other securities
Amortized cost and fair values of investment securities available-for-sale
Amortized Cost	878	928
Unrealized Gain	0	0
Unrealized Loss	0	0
Investment securities available-for-sale	$ 878	$ 928

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

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

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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
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-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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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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