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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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Date the equity-based award expires, in CCYY-MM-DD format.

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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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No definition available.

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

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No definition available.

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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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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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STOCK OPTION AWARDS DURING PERIOD (Details 3) - Stock options [Member] - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining recognition period (years)	0 years
Shares granted	0
Weighted average grant date fair value of options granted (per share)	$ 0	$ 13.46	$ 12.43
Options Granted Date Three [Member] \| 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		5,000
Vesting period		21 months
Investment Options, Expiration Date		Apr. 03, 2028
Expected volatility		21.15%
Expected life (years)		5 years 6 months
Expected dividend yield		1.94%
Risk free interest rate		2.62%
Weighted average grant date fair value of options granted (per share)		$ 13.46
Options Granted Date Two [Member] \| 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			5,000
Vesting period			14 months
Investment Options, Expiration Date			Nov. 07, 2027
Expected volatility			20.80%
Expected life (years)			5 years 6 months
Expected dividend yield			1.87%
Risk free interest rate			2.02%
Weighted average grant date fair value of options granted (per share)			$ 12.43