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STOCK BASED COMPENSATION (Details Textual) - $ / shares | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  | 177,191 |  | 212,698 |
Share Based Compensation Arrangement By Share Based Payment Award Options Price Per Share Common Stock Average High And Low Price Intrinsic Value |  | $ 70.95 |  |  |
Stock options [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number |  | 84,000 | [1] | 109,650 |
Options outstanding and expected to vest at December 31, 2017 | [2] | 84,000 |  |  |
Annualized estimated forfeitures |  |  |  | 4.50% | 4.50%
Options exercisable at December 31, 2017 | [3] | 79,001 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares |  | 4,999 |  | 6,666 |
Weighted average remaining recognition period (years) |  | 1 year |  |  |
Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  | 225,965 | [4] | 264,315 |
Weighted average remaining recognition period (years) |  | 3 years |  |  |
Director [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number |  | 38,000 |  |  |
Options outstanding and expected to vest at December 31, 2017 | [1] | 38,000 |  |  |
Options exercisable at December 31, 2017 | [1] | 33,001 |  |  |
Director [Member] | Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number |  | 38,445 |  |  |
Two Thousand Five Amended and Restated Employee Stock Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  | 1,650,000 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant |  | 416,513 |  |  |
Two Thousand Ten Nonemployee Director Stock Plan [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized |  | 314,600 |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant |  | 179,355 |  |  |
Two Thousand Ten Nonemployee Director Stock Plan [Member] | Maximum [Member] | Restricted Stock [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period |  | 5 years |  |  |
[1] | Inclusive of 38,000 stock options outstanding to Directors.
[2] | Inclusive of 38,000 vested stock options and expected to vest to Directors.
[3] | Inclusive of 33,001 vested stock options outstanding to Directors.
[4] | Inclusive of 38,445 restricted stock awards outstanding to Directors.

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- Definition Share Based Compensation Arrangement By Share Based Payment Award Options Price Per Share Common Stock Average High And Low Price Intrinsic Value + References No definition available. + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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