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, 2019	Sep. 30, 2018	Dec. 31, 2018
Mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	$ 29,363	$ 23,248
Originations	654	4,322
Amortization	(2,867)	(4,394)
Sale of mortgage servicing rights	(20,556)	0
Acquired mortgage servicing rights	0	6,995
Valuation allowance	(1,572)	0
Balance at end of period	$ 5,022	$ 30,171
Servicing rights, net to servicing portfolio	0.81%	0.73%
Commercial servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Balance at beginning of period	$ 1,709	$ 2,609
Originations	102	82
Amortization	(555)	(835)
Valuation allowance on commercial servicing rights	(7)	12
Balance at end of period	1,249	1,868
Fair value of servicing rights	$ 1,827	$ 2,529	$ 2,100
Servicing rights, net to servicing portfolio	1.44%	1.63%

Commercial Servicing Rights (CSR) Impairment (Recovery)

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- Definition

Servicing Asset, Net to Servicing Portfolio, Percentage

+ References

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)
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-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

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
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-Section 50
-Paragraph 4
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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

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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

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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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

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