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Significant Accounting Policies (Details Textual) $ in Thousands | 6 Months Ended
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Jun. 30, 2018 USD ($) segment shares | Jun. 30, 2017 USD ($) shares
Accounting Policies [Abstract] |  |
Number of Reportable Segments | segment | 1 |
Vesting period | 3 years |
Incremental vesting rights for first year (as a percent) | 33.00% |
Incremental vesting rights for second year (as a percent) | 33.00% |
Incremental vesting rights for third year (as a percent) | 34.00% |
Number of shares awarded | shares | 17,220 | 16,562
Grant date value | $ | $ 784 | $ 773

X
- Definition The total fair value at grant date for nonvested equity-based awards issued 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), net of estimated forfeitures. + References No definition available. + Details
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Period Type: | instant

X
- Definition Description of award terms as to how many incremental shares or portion of an award will vest in second year and will no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage. + References No definition available. + Details
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- Definition Description of award terms as to how many incremental shares or portion of an award will vest in third year and will no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage. + References No definition available. + Details
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- Definition Description of award terms as to how many shares or portion of an award will vest in first year and will no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, shown as a percentage. + References No definition available. + Details
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- References No definition available. + Details
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- Definition Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. + References No definition available. + 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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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- Definition 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). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
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