STOCK-BASED COMPENSATION (Analysis of Restricted Stock Award Activity) (Details) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 USD ($)
Weighted-Average Grant Date Fair Value
Allocated share-based compensation expense \| $	$ 5,249	$ 4,808	$ 3,696
Restricted Stock Awards
Shares
Non-vested at beginning of period (in shares) \| shares	267,799
Granted (in shares) \| shares	79,739
Vested (in shares) \| shares	(40,362)
Forfeited (in shares) \| shares	(23,201)
Non-vested at end of period (in shares) \| shares	283,975	267,799
Weighted-Average Grant Date Fair Value
Non-vested at beginning of period (in dollars per share) \| $ / shares	$ 36.66
Granted (in dollars per share) \| $ / shares	46.02
Vested (in dollars per share) \| $ / shares	33.95
Forfeited (in dollars per share) \| $ / shares	33.86
Non-vested at end of period (in dollars per share) \| $ / shares	$ 39.90	$ 36.66
Allocated share-based compensation expense \| $	$ 3,877	$ 2,987	$ 1,766
Total compensation expense that has yet to be recognized \| $	4,589
Intrinsic value of the unvested restricted stock awards outstanding \| $	$ 15,746	$ 12,206

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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

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Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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

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Intrinsic value of equity-based compensation awards not vested. Excludes stock and unit options.

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