STOCK BASED COMPENSATION - Other (Details)	12 Months Ended
Dec. 31, 2019 USD ($) item	Dec. 31, 2018 USD ($) $ / shares	Dec. 31, 2017 USD ($) shares
STOCK BASED COMPENSATION
Compensation cost	$ 1,526,000	$ 1,499,000	$ 718,000
Stock Options
STOCK BASED COMPENSATION
Expected volatility		21.30%
Expected term		6 years 6 months
Dividend yield		3.00%
Risk free rate		2.90%
Weighted average fair value of each option granted \| $ / shares		$ 11.90
Compensation cost	476,000	$ 238,000	0
Total unrecognized compensation cost	$ 714,000	1,200,000
Cost is expected to be recognized over a weighted-average period	1 year 6 months
Aggregate Intrinsic value, Outstanding	$ 1,154,000	912,000
Aggregate Intrinsic value, Exercised			$ 708,000
Stock options exercised \| shares			260,000
Restricted Stock
STOCK BASED COMPENSATION
Compensation cost	1,000,000	1,300,000	$ 718,000
Total unrecognized compensation cost	$ 1,100,000	1,500,000
Cost is expected to be recognized over a weighted-average period	1 year 9 months 18 days
Grant date fair value of shares vested during period	$ 1,100,000	$ 1,100,000
Officers and employees \| Restricted Stock
STOCK BASED COMPENSATION
Vesting Percentage	33.00%
Number of anniversaries of the grant date \| item	3
Directors \| Vest on grant date \| Restricted Stock
STOCK BASED COMPENSATION
Vesting Percentage	25.00%
Directors \| Vest on each of the first three anniversaries of the grant date \| Restricted Stock
STOCK BASED COMPENSATION
Vesting Percentage	25.00%

Represents the number of anniversaries of grant date on which share-based compensation awards vest.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for option under share-based payment arrangement.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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Percentage of vesting of award under share-based payment arrangement.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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

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