STOCK BASED COMPENSATION PLANS - Status of Company's Stock Options (Details) $ / shares in Units, $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($) $ / shares shares
Number of Options
Outstanding, January 1, 2019 \| shares	47,393
Granted \| shares	63,267
Outstanding, March 31, 2019 \| shares	110,660
Vested and Exercisable, March 31, 2019 \| shares	15,795
Weighted Average Exercise Price
Weighted Average Exercise Price, January 1, 2019 \| $ / shares	$ 36.19
Granted \| $ / shares	35.35
Weighted Average Exercise Price, March, 2019 \| $ / shares	35.71
Vested and Exercisable, March 31, 2019 \| $ / shares	$ 36.19
Weighted Average Remaining Contractual Life, Outstanding	9 years 4 months 24 days
Weighted Average Remaining Contractual Life, Vested and Exercisable	8 years 10 months 24 days
Aggregate Intrinsic Value, Outstanding \| $	$ 0
Aggregate Intrinsic Value, Vested and Exercisable \| $	$ 0

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

No definition available.

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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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- Definition

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

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- Definition

Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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- Definition

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

+ References

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for fully vested and expected to vest exercisable or convertible options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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