The maximum amount of compensation expense incurred on the reporting period.

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- Definition

Estimated amount of compensation expense excepted to be recorded.

+ References

No definition available.

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- Definition

Description about Option subscription percentage during period.

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No definition available.

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- Definition

The Maximum Option vested as percentage of total option grant during the year.

+ References

No definition available.

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- Definition

Description about the Period in which option vested or expired.

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No definition available.

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- Definition

Unrecognized compensation expense of reporting period.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

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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
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

+ References

No definition available.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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Stock Compensation Plans (Details Textual) - USD ($)	3 Months Ended			6 Months Ended		12 Months Ended
Stock Compensation Plans (Details Textual) - USD ($)	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number	39,400			39,400		86,900
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options	$ 77,000			$ 77,000
Employee Service Share Based Compensation Nonvested Awards, Total Compensation Cost Not Yet Recognized, Period For Recognition (in years)				1 year 10 months 24 days
Allocated Share-based Compensation Expense	343,000		$ 266,000	$ 907,000	$ 1,100,000
Compensation Expense, Maximum	4,300,000			4,300,000
Estimated Compensation Expense, Excepted	3,500,000			3,500,000
Unrecognized Compensation Expense	$ 1,800,000			$ 1,800,000
Share-based Compensation Award, Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				4,104
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				7,348
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number	144,606			144,606
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period				29,872
Restricted Stock Units (RSUs) [Member] \| Share-based Compensation Award, Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				8,000
Short-term Equity Incentive Plan 2013 [Member]
Stock Option Period, Description				All options expire ten years from the date of grant. Vested options of retirees expire on the earlier of the scheduled expiration date or three months after the retirement date.
Equity Plan 2010 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized	900,000			900,000
Short Term Equity Incentive Plan 2014 [Member]
Option Subscription, Description				The final amount of benefits under the STIPs is determined as of December 31 of the same year and paid out in cash in the first quarter of the following year.
Long Term Equity Incentive Plan 2014 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross		49,514
Option Subscription, Description				The amount of benefit under each LTIP will be determined individually at the end of the 36 month performance period ending December 31. The benefits earned under each LTIP will be paid out in equity in the first quarter following the end of the performance period. The participants are required to be employed on the day of payout in order to receive such payment.
Long Term Equity Incentive Plan 2015 [Member]
Option Subscription, Description				The amount of benefit under each LTIP will be determined individually at the end of the 36 month performance period ending December 31. The benefits earned under each LTIP will be paid out in equity in the first quarter following the end of the performance period. The participants are required to be employed on the day of payout in order to receive such payment.
Short Term Equity Incentive Plan 2015 [Member]
Option Subscription, Description				The final amount of benefits under the STIPs is determined as of December 31 of the same year and paid out in cash in the first quarter of the following year.
Long Term Equity Incentive Plan 2016 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				49,052
Long Term Equity Incentive Plan 2016 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	45.00%			45.00%
Short Term Equity Incentive Plan 2016 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	10.00%			10.00%
Long Term Equity Incentive Plan 2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				41,314
Long Term Equity Incentive Plan 2017 [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	20.00%			20.00%
Short Term Equity Incentive Plan 2017 [Member]
Allocated Share-based Compensation Expense				$ 384,000		$ 774,000
Short Term Equity Incentive Plan 2017 [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate	45.00%			45.00%
Stock Option Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Vested Percentage, Year				20.00%
Restricted Stock Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				12,104
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				19,452
Long Term Equity Incentive Plan 2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross				41,676