Shareholders' Equity (Details 1)	12 Months Ended
Dec. 31, 2017 $ / shares shares
Options outstanding December 31, 2017
Number outstanding \| shares	679,552
Options exercisable at December 31, 2017
Number exercisable \| shares	254,850
Stock options [Member] \| 2.71-3.90 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Minimum exercise price	$ 2.71
Maximum exercise price	$ 3.90
Options outstanding December 31, 2017
Number outstanding \| shares	25,000
Weighted average exercise price	$ 3.21
Weighted average remaining contractual life (In years)	11 months 12 days
Options exercisable at December 31, 2017
Number exercisable \| shares	25,000
Weighted average exercise price	$ 3.21
Weighted average remaining contractual life (In years)	11 months 12 days
Stock options [Member] \| 5.35-8.60 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Minimum exercise price	$ 5.35
Maximum exercise price	$ 8.60
Options outstanding December 31, 2017
Number outstanding \| shares	47,800
Weighted average exercise price	$ 6.87
Weighted average remaining contractual life (In years)	1 year 6 months 29 days
Options exercisable at December 31, 2017
Number exercisable \| shares	47,800
Weighted average exercise price	$ 6.87
Weighted average remaining contractual life (In years)	1 year 6 months 29 days
Stock options [Member] \| 10.49 - 14.52 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Minimum exercise price	$ 10.49
Maximum exercise price	$ 14.52
Options outstanding December 31, 2017
Number outstanding \| shares	427,750
Weighted average exercise price	$ 11.87
Weighted average remaining contractual life (In years)	3 years 1 month 24 days
Options exercisable at December 31, 2017
Number exercisable \| shares	182,050
Weighted average exercise price	$ 12.19
Weighted average remaining contractual life (In years)	2 years 8 months 26 days
Stock options [Member] \| 18.90-19.85 [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Minimum exercise price	$ 18.90
Maximum exercise price	$ 19.85
Options outstanding December 31, 2017
Number outstanding \| shares	179,002
Weighted average exercise price	$ 19.48
Weighted average remaining contractual life (In years)	4 years 7 months 13 days
Options exercisable at December 31, 2017
Number exercisable \| shares
Weighted average exercise price

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Options Outstanding [Abstract]

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ 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 (g)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

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- Definition

Weighted average exercise price as of the balance sheet date for those equity-based payment arrangements exercisable and outstanding.

+ 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)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average remaining contractual term of exercisable stock options, 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 (e)(2)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ 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)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average remaining contractual term of outstanding stock options, 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 (e)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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