GOODWILL, CORE DEPOSIT PREMIUM AND OTHER INTANGIBLE ASSETS (Estimated future amortization expense for amortizable intangible assets) (Details) $ in Thousands	Mar. 31, 2022 USD ($)
Future amortization expense for amortizable intangible assets [Line Items]
Nine months ending December 31, 2022	$ 6,991
Year ending December 31,
2023	8,470
2024	7,080
2025	5,945
2026	4,503
2027	3,329
Thereafter	2,718
Total	39,036
Core Deposit Intangibles
Future amortization expense for amortizable intangible assets [Line Items]
Nine months ending December 31, 2022	5,656
Year ending December 31,
2023	6,739
2024	5,591
2025	4,700
2026	3,533
2027	2,601
Thereafter	1,990
Total	30,810
Customer Relationship Intangibles
Future amortization expense for amortizable intangible assets [Line Items]
Nine months ending December 31, 2022	26
Year ending December 31,
2023	33
2024	33
2025	32
2026	0
2027	0
Thereafter	0
Total	124
Mortgage Servicing Rights
Future amortization expense for amortizable intangible assets [Line Items]
Nine months ending December 31, 2022	1,309
Year ending December 31,
2023	1,698
2024	1,456
2025	1,213
2026	970
2027	728
Thereafter	728
Total	$ 8,102

Future amortization expense for amortizable intangible assetse [Line Items]

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Amount of amortization for asset, excluding financial asset and goodwill, lacking physical substance with finite life expected to be recognized after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in remainder of current fiscal year.

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=120154696&loc=d3e54445-107959

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