Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, 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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Date the equity-based award expires, in CCYY-MM-DD format.

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- Definition

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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- Definition

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

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- Definition

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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- Definition

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

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No definition available.

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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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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the 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
-SubTopic 10
-Section 50
-Paragraph 2
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-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-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, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average remaining recognition period (years)	1 year
Shares granted	5,000
Weighted average grant date fair value of options granted (per share)	$ 13.46	$ 12.43	$ 11.03
2/20/2016 \| 2010 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			5,000
Vesting period			22 months
Investment Options, Expiration Date			Feb. 20, 2026
Expected volatility			32.44%
Expected life (years)			5 years 6 months
Expected dividend yield			2.28%
Risk free interest rate			1.29%
Weighted average grant date fair value of options granted (per share)			$ 10.59
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		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
Options Granted Date Three [Member] \| Two Thousand Eighteen Nonemployee Director Stock 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			18 months
Investment Options, Expiration Date			Jul. 14, 2026
Expected volatility			32.28%
Expected life (years)			5 years 6 months
Expected dividend yield			2.37%
Risk free interest rate			1.14%
Weighted average grant date fair value of options granted (per share)			$ 11.46