FAIR VALUES OF ASSETS AND LIABILITIES - Quantitative Information About Recurring Level 3 Fair Value Measurements (Details) $ in Thousands	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Total investment securities available-for-sale	$ 1,257,101	$ 1,751,832
Trust Preferred Securities \| Valuation Technique, Discounted Cash Flow
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Total investment securities available-for-sale	$ 31	$ 43
Trust Preferred Securities \| Valuation Technique, Discounted Cash Flow \| Minimum
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Debt Securities, Available-for-Sale, Measurement Input		0.0235
Trust Preferred Securities \| Valuation Technique, Discounted Cash Flow \| Minimum \| Measurement Input, Default Rate
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Debt Securities, Available-for-Sale, Measurement Input	0.0698
Trust Preferred Securities \| Valuation Technique, Discounted Cash Flow \| Maximum
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Debt Securities, Available-for-Sale, Measurement Input		0.0247
Trust Preferred Securities \| Valuation Technique, Discounted Cash Flow \| Maximum \| Measurement Input, Default Rate
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Debt Securities, Available-for-Sale, Measurement Input	0.0719
Municipal securities
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Total investment securities available-for-sale	$ 457,857	$ 708,502
Municipal securities \| Valuation Technique, Discounted Cash Flow
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Total investment securities available-for-sale	$ 15,117	$ 20,123
Municipal securities \| Valuation Technique, Discounted Cash Flow \| Minimum
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Debt Securities, Available-for-Sale, Measurement Input	0.0300	0.0050
Municipal securities \| Valuation Technique, Discounted Cash Flow \| Maximum
Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]
Debt Securities, Available-for-Sale, Measurement Input	0.0400	0.0190

Quantitative Information About Recurring Level 3 Fair Value Measurements [Line Items]

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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- Definition

Value of input used to measure 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 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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