STOCK AWARD PLANS, Director Plan Stock Option Activity (Details) - Director Plan [Member]	3 Months Ended
Mar. 31, 2019 $ / shares shares
Stock Award Plan Information [Abstract]
Shares available for future grants (in shares)	486,058
Stock Options [Member]
Stock Award Plan Information [Abstract]
Term of grant	10 years
Outstanding Non-Qualified or Nonincentive Stock Options [Roll Forward]
Outstanding at Period Start (in shares)	131,104
Exercised (in shares)	(6,000)
Outstanding at Period End (in shares)	125,104
Weighted Average Exercise Price [Abstract]
Outstanding at Period Start (in dollars per share) \| $ / shares	$ 70.14
Exercised (in dollars per share) \| $ / shares	29.60
Outstanding at Period End (in dollars per share) \| $ / shares	$ 72.08
Restricted Stock [Member]
Stock Award Plan Information [Abstract]
Vesting period	6 months

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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 option holders acquired shares when converting their stock options into shares.

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Number of share options (or share units) exercised during the current period.

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