Number of common shares originally reserved for future issuance under the applicable stock option plan(s).

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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No definition available.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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No definition available.

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

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Number of shares that have been repurchased and retired during the period.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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STOCK-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchased and retired during period, shares			67,974	17,300
Average cost per share of stock repurchased			$ 27.34	$ 22.14
Recognized compensation expense	$ 296	$ 218	$ 508	$ 542
Recognized compensation expense, net of tax	$ 192	$ 142	$ 330	$ 353
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock shares vested during period (in shares)			85,192
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock awards or units granted during period (in shares)			116,288
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercised during period (in shares)			163,658
Weighted average exercise price of options exercised during period (in dollars per share)			$ 14.76
Non-Employee Director [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock awards or units granted during period (in shares)			2,000
EMC Insurance Group Inc Non-Employee Director 2017 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Registered shares (in shares)	150,000		150,000