FAIR VALUE OF FINANCIAL INSTRUMENTS- Fair value option and gains and losses from fair value changes (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Fair Value, Option, Quantitative Disclosures [Line Items]
Aggregate fair value	$ 113,852		$ 16,431
Difference	715		652
Contractual principal	113,137		15,779
Gains and losses from fair value changes
Gains and losses from fair value changes of loan held for sales	97	$ (385)
Commercial Portfolio
Fair Value, Option, Quantitative Disclosures [Line Items]
Aggregate fair value	1,706		8,236
Difference	48		206
Contractual principal	1,658		8,030
Gains and losses from fair value changes
Gains and losses from fair value changes of loan held for sales	(158)	(328)
Residential real estate:
Fair Value, Option, Quantitative Disclosures [Line Items]
Aggregate fair value	12,458		8,195
Difference	667		446
Contractual principal	11,791		$ 7,749
Gains and losses from fair value changes
Gains and losses from fair value changes of loan held for sales	255	$ (57)
Consumer
Fair Value, Option, Quantitative Disclosures [Line Items]
Aggregate fair value	99,688
Contractual principal	$ 99,688

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due, in nonaccrual status, or both.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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The face amount of loans that will be sold to other entities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
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