STOCK-BASED COMPENSATION PLAN Restricted Stock Activity (Details) - $ / shares	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Weighted Average Fair Value
Weighted average fair value nonvested shares-beginning balance (in dollars per share)	$ 29.57
Weighted average fair value nonvested shares - granted during the period (in dollars per share)	31.03
Weighted average fair value nonvested shares - cancelled/forfeited during the period (in dollars per share)	31.58
Weighted average fair value nonvested shares - vested during the period (in dollars per share)	26.09
Weighted average fair value nonvested shares - ending balance (in dollars per share)	$ 31.50
Officers & Key Employees
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested Shares Outstanding, Beginning Balance	411,809
Granted (in shares)	184,791
Cancelled/Forfeited (in shares)	(38,788)
Vested (in shares)	(149,082)
Nonvested Shares Outstanding, Ending Balance	408,730
Directors
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Nonvested Shares Outstanding, Beginning Balance	26,416
Granted (in shares)	30,961	30,394
Cancelled/Forfeited (in shares)	0
Vested (in shares)	(26,416)
Nonvested Shares Outstanding, Ending Balance	30,961

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Weighted average price of options that were either forfeited or expired.

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