FAIR VALUE - Inputs and Valuation technique (Details)	Dec. 31, 2019	Dec. 31, 2018
Fair value measurement inputs and valuation techniques
Valuation technique of available for sale securities	us-gaap:ValuationTechniqueDiscountedCashFlowMember	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Valuation technique of servicing asset	us-gaap:ValuationTechniqueDiscountedCashFlowMember	us-gaap:ValuationTechniqueDiscountedCashFlowMember
Discount Rate
Fair value measurement inputs and valuation techniques
Servicing asset measurement input	14
Discount Rate \| Minimum
Fair value measurement inputs and valuation techniques
Servicing asset measurement input		11
Discount Rate \| Minimum \| Obligations of U.S. Government entities and agencies
Fair value measurement inputs and valuation techniques
Available for sale securities measurement input	0	0
Discount Rate \| Minimum \| SBA servicing assets and Interest only strip
Fair value measurement inputs and valuation techniques
Available for sale securities measurement input	5.80
Servicing asset measurement input		8.78
Discount Rate \| Maximum
Fair value measurement inputs and valuation techniques
Servicing asset measurement input		14
Discount Rate \| Maximum \| Obligations of U.S. Government entities and agencies
Fair value measurement inputs and valuation techniques
Available for sale securities measurement input	3	3
Discount Rate \| Maximum \| SBA servicing assets and Interest only strip
Fair value measurement inputs and valuation techniques
Available for sale securities measurement input	12.06	14.56
Prepayment speed
Fair value measurement inputs and valuation techniques
Servicing asset measurement input	16	15
Prepayment speed \| Minimum \| SBA servicing assets and Interest only strip
Fair value measurement inputs and valuation techniques
Available for sale securities measurement input	10.82
Servicing asset measurement input		6.82
Prepayment speed \| Maximum \| SBA servicing assets and Interest only strip
Fair value measurement inputs and valuation techniques
Available for sale securities measurement input	16.54	12.87

Value of input used to measure investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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=117815213&loc=d3e19207-110258

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Period Type:	instant

- Definition

Indicates type of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

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

No definition available.

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- Definition

Value of input used to measure servicing asset.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant

- Definition

Indicates measurement input for 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)(1)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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