Stock Option Programs and Share-based Compensation Expense (Details Textual) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share Based Compensation Arrangement by Share Based Payment Award Options Granted for Award	6,000
Share Based Compensation Arrangement By Share Based Payment Award Shares Annual Grant Purchased Forward	2,000
Share Based Compensation Arrangement By Share Based Payment Award Additional Shares Purchased Forward	1,500
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant		450,000
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Increased For Discretionary Stock Options		100,000
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	4 years
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value	$ 87,000
Gronau Agreement [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross	150,000
Share-based Compensation Arrangement by Share-based Payment Award, Terms of Award	10 Years
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Share Based Compensation Arrangement By Share Based Payment Award Vested Year One	20,000
Share Based Compensation Arrangement By Share Based Payment Award Vested Year Two	30,000
Share Based Compensation Arrangement By Share Based Payment Award Vested Year Three	30,000
Share Based Compensation Arrangement By Share Based Payment Award Vested Year Four	30,000
Share Based Compensation Arrangement By Share Based Payment Award Vested Year Five	40,000

The additional number of options granted on the open market during the period for issuance to employees under the plan.

No definition available.

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- Definition

Number of shares increased for discretionary stock options during the period.

+ References

No definition available.

+ Details

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- Definition

The number of options granted on the open market during the period for issuance to employees under the plan.

+ References

No definition available.

+ Details

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- Definition

The number of options granted for annual grant to purchase of shares during the period.

+ References

No definition available.

+ Details

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- Definition

Number of shares vested in fifth year

+ References

No definition available.

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- Definition

Number of shares vested in fourth year.

+ References

No definition available.

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- Definition

Number of shares vested in first year.

+ References

No definition available.

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- Definition

Number of shares vested in third year.

+ References

No definition available.

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- Definition

Number of shares vested in second year.

+ References

No definition available.

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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=6415400&loc=d3e5070-113901

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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.

+ References

No definition available.

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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=6415400&loc=d3e5070-113901

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ 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 (d)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Description of pertinent provisions of equity-based compensation awards that have actual or potential impact upon the company's financial statements.

+ 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)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period from grant date that an equity-based award expires, 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)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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