Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

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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.

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
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Fixed interest rate related to the interest rate derivative.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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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The number of derivative instruments of a particular group held by the entity.

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Variable interest rate in effect as of the balance sheet date related to the interest rate derivative.

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The net gain (loss) recognized in earnings during the reporting period representing the amount of the cash flow hedges' ineffectiveness.

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The amount of interest income and other income recognized during the period. Included in this element is interest derived from investments in debt securities, cash and cash equivalents, and other investments which reflect the time value of money or transactions in which the payments are for the use or forbearance of money and other income from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business).

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The net amount of operating interest income (expense).

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount of unrealized gain (loss) related to derivatives designated as cash flow hedging instruments, recorded in results of operations to the extent that the cash flow hedge is determined to be ineffective.

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DERIVATIVES (Details)	3 Months Ended			9 Months Ended		12 Months Ended
DERIVATIVES (Details)	Sep. 30, 2018 USD ($) N	Mar. 31, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) N	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($) N
Derivative [Line Items]
Net interest income (expense)	$ 28,142,000		$ 29,992,000	$ 85,778,000	$ 82,555,000
Amount of gain/(loss) recognized in OCI (effective portion)	843,000		222,000	2,412,000	1,023,000
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional Amount	$ 230,000,000			$ 230,000,000		$ 180,000,000
Weighted average pay rate	2.04%			2.04%		1.64%
Weighted average receive rate	2.07%			2.07%		1.33%
Weighted average maturity				2 years 10 months 24 days		2 years 3 months
Unrealized gain, net				$ 3,536,000		$ 1,394,000
Number of contracts \| N	11			11		9
Net interest income (expense)	$ 124,000		(150,000)	$ 137,000	(763,000)
Amount of gain/(loss) recognized in OCI (effective portion)	514,000		131,000	1,597,000	605,000
Amount of gain/(loss) reclassified from OCI to interest expense	20,000		0	64,000	0
Amount of gain/(loss) recognized in other non-interest expense	0		$ 0	0	$ 0
Unrealized after-tax gain of accumulated other comprehensive income loss		$ 220,000
Interest income	31,000			93,000
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Other Assets [Member]
Derivative [Line Items]
Notional Amount	230,000,000			230,000,000		$ 180,000,000
Fair Value	3,536,000			3,536,000		1,394,000
Loan Level Swaps [Member] \| Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Notional Amount	$ 425,151,000			$ 425,151,000		$ 317,363,000
Weighted average pay rate	4.28%			4.28%		4.11%
Weighted average receive rate	4.05%			4.05%		3.43%
Weighted average maturity				7 years 6 months		7 years 7 months 6 days
Number of contracts \| N	57			57		42
Fair Value	$ 12,027,000			$ 12,027,000		$ 3,131,000