DERIVATIVE FINANCIAL INSTRUMENTS - Summary of Interest Rate Swaps Outstanding (Details) - Not Designated as Hedging Instrument - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Interest Rate Swaps \| Customer
Derivative [Line Items]
Receive fixed/pay floating, Notional amount	$ 173,304	$ 185,637
Receive fixed/pay floating, Fair value	$ 880	$ 609
Interest Rate Swaps \| Customer \| LIBOR
Derivative [Line Items]
Maturity	2 years 9 months 18 days	3 years 4 months 24 days
Interest Rate Swaps \| Customer \| LIBOR \| Minimum
Derivative [Line Items]
Fixed rate, Rate range	2.19%	2.19%
Floating rate spread, Range	0.00%	0.00%
Interest Rate Swaps \| Customer \| LIBOR \| Maximum
Derivative [Line Items]
Fixed rate, Rate range	5.72%	5.72%
Floating rate spread, Range	4.25%	4.25%
Interest Rate Swaps \| Correspondent
Derivative [Line Items]
Pay fixed/receive floating, Notional amount	$ 173,304	$ 185,637
Pay fixed/receive floating, Fair value	$ (901)	$ (691)
Interest Rate Swaps \| Correspondent \| LIBOR
Derivative [Line Items]
Maturity	2 years 9 months 18 days	3 years 4 months 24 days
Interest Rate Swaps \| Correspondent \| LIBOR \| Minimum
Derivative [Line Items]
Fixed rate, Rate range	2.19%	2.19%
Floating rate spread, Range	0.00%	0.00%
Interest Rate Swaps \| Correspondent \| LIBOR \| Maximum
Derivative [Line Items]
Fixed rate, Rate range	5.72%	5.72%
Floating rate spread, Range	4.25%	4.25%
Interest Rate Caps and Collars \| Customer
Derivative [Line Items]
Receive fixed/pay floating, Notional amount	$ 37
Receive fixed/pay floating, Fair value	$ 0
Interest Rate Caps and Collars \| Customer \| LIBOR
Derivative [Line Items]
Maturity	1 year 8 months 12 days
Interest Rate Caps and Collars \| Customer \| LIBOR \| Minimum
Derivative [Line Items]
Fixed rate, Rate range	4.55%
Floating rate spread, Range	3.00%
Interest Rate Caps and Collars \| Customer \| LIBOR \| Maximum
Derivative [Line Items]
Fixed rate, Rate range	6.00%
Floating rate spread, Range	3.75%
Interest Rate Caps and Collars \| Correspondent
Derivative [Line Items]
Pay fixed/receive floating, Notional amount	$ 37
Pay fixed/receive floating, Fair value	$ 0
Interest Rate Caps and Collars \| Correspondent \| LIBOR
Derivative [Line Items]
Maturity	1 year 8 months 12 days
Interest Rate Caps and Collars \| Correspondent \| LIBOR \| Minimum
Derivative [Line Items]
Fixed rate, Rate range	4.55%
Floating rate spread, Range	3.00%
Interest Rate Caps and Collars \| Correspondent \| LIBOR \| Maximum
Derivative [Line Items]
Fixed rate, Rate range	6.00%
Floating rate spread, Range	3.75%
Interest Rate Caps \| Customer
Derivative [Line Items]
Receive fixed/pay floating, Notional amount		$ 16
Receive fixed/pay floating, Fair value		$ 0
Interest Rate Caps \| Customer \| LIBOR
Derivative [Line Items]
Fixed rate, Rate range		6.00%
Floating rate spread, Range		3.00%
Maturity		2 years
Interest Rate Caps \| Correspondent
Derivative [Line Items]
Pay fixed/receive floating, Notional amount		$ 16
Pay fixed/receive floating, Fair value		$ 0
Interest Rate Caps \| Correspondent \| LIBOR
Derivative [Line Items]
Fixed rate, Rate range		6.00%
Floating rate spread, Range		3.00%
Maturity		2 years

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Notional Amount
-URI http://asc.fasb.org/extlink&oid=6519104

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5580258-113959

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- Definition

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

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Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313

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Fair value, after offset of derivative asset, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, elected not to be and before offset against a right to receive collateral under a master netting arrangement. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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- Definition

Fixed interest rate related to the interest rate derivative.

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No definition available.

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- Definition

Nominal or face amount used to calculate payments on the derivative liability.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

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