GOODWILL, CORE DEPOSIT PREMIUM AND OTHER INTANGIBLE ASSETS (Mortgage loans servicing) (Details) - Mortgage servicing rights $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Mar. 31, 2021
Valuation servicing rights in tranches [Line Items]
Average constant prepayment rate (as a percent)	9.80%	13.40%
Servicing assets, discount rate (as a percent)	9.01%	9.02%
Fair value of mortgage servicing rights	$ 8,496	$ 6,412
Minimum \| Measurement Input, Cap Rate
Valuation servicing rights in tranches [Line Items]
Average capitalization rate (percent)	0.0083		0.0076
Maximum \| Measurement Input, Cap Rate
Valuation servicing rights in tranches [Line Items]
Average capitalization rate (percent)	0.0111		0.0112

Valuation servicing rights in tranches [Line Items]

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- Definition

Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122739-111746

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=7516967&loc=d3e66267-113978

+ Details

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- Definition

Value of input used to measure servicing asset.

+ 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 http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

+ Details

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- Definition

Discount rate used to estimate the fair value of servicing assets and servicing liabilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 2
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=125521744&loc=d3e122596-111746

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- Definition

Estimated rate of prepayments of principal on servicing assets and servicing liabilities.

+ References

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