INVESTMENT SECURITIES - Realized Gains and Losses on Sales of Securities (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Gross realized gains and losses
Debt securities, available-for-sale, gross realized gains	$ 731	$ 1,615	$ 657
Debt securities, available-for-sale, gross realized losses	32	23	17
Equity securities, gross realized gains	0	0	52
Equity securities, gross realized losses	0	0	0
U.S. Government and agency securities
Gross realized gains and losses
Debt securities, available-for-sale, gross realized gains	0	0	0
Debt securities, available-for-sale, gross realized losses	0	0	0
Mortgage-backed securities
Gross realized gains and losses
Debt securities, available-for-sale, gross realized gains	0	83	0
Debt securities, available-for-sale, gross realized losses	0	0	1
State and political securities
Gross realized gains and losses
Debt securities, available-for-sale, gross realized gains	408	978	544
Debt securities, available-for-sale, gross realized losses	32	23	11
Other debt securities
Gross realized gains and losses
Debt securities, available-for-sale, gross realized gains	323	554	113
Debt securities, available-for-sale, gross realized losses	0	0	5
Financial institution equity securities
Gross realized gains and losses
Equity securities, gross realized gains	0	0	52
Equity securities, gross realized losses	0	0	0
Other equity securities
Gross realized gains and losses
Equity securities, gross realized gains	0	0	0
Equity securities, gross realized losses	$ 0	$ 0	$ 0

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- Definition

Amount of realized 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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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- Definition

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

+ References

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- Definition

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

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Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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