STOCK BASED PLANS (Summary of Stock Option Activity) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Stock Options
Stock options outstanding at the beginning of the period (in shares)	817,998
Granted (in shares)	9,500
Forfeited (in shares)	(4,600)
Stock options outstanding at the end of the period (in shares)	822,898
Weighted Average Exercise Price
Stock options outstanding at the beginning of the period (in dollars per share)	$ 105.06
Granted (in dollars per share)	110.35
Forfeited (in dollars per share)	121.04
Stock options outstanding at the end of the period (in dollars per share)	$ 105.06
Stock based compensation expense	$ 3,069	$ 2,684
Stock Option
Weighted Average Exercise Price
Stock based compensation expense	700	700
Share based compensation costs capitalized	$ 200	$ 300

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

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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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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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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