GOODWILL, CORE DEPOSIT PREMIUM AND OTHER INTANGIBLE ASSETS (Changes in capitalized mortgage and commercial servicing rights) (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	$ 5,621	$ 29,363
Originations	2,571	654
Amortization	(1,693)	(2,867)
Sale of mortgage servicing rights	0	(20,556)
Valuation allowance	(1,676)	(1,572)
Balance at end of period	$ 4,823	$ 5,022
Servicing rights, net to servicing portfolio	0.68%	0.81%
Commercial servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	$ 1,115	$ 1,709
Originations	62	102
Amortization	(248)	(555)
Valuation allowance	0	(7)
Balance at end of period	929	1,249
Fair value of mortgage servicing rights	$ 1,497	$ 1,827	$ 1,600
Servicing rights, net to servicing portfolio	1.31%	1.44%

Servicing Asset, Net to Servicing Portfolio, Percentage

No definition available.

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- Definition

The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 4
-Subparagraph (a)(6)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746

+ Details

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- Definition

Amortized amount 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122492-111745

Reference 3: http://www.xbrl.org/2003/role/recommendedDisclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6469459&loc=d3e122501-111745

+ Details

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- Definition

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

+ References

+ Details

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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

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Decrease in servicing assets subsequently measured at fair value resulting from conveyance of servicing rights to unrelated parties.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

+ Details

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- Definition

Amount of increase (decrease) from changes in fair value classified as other for a 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 3
-Subparagraph (a)(4)(ii)
-URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122625-111746

+ Details

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- Details

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