Shareholders' Equity (Details 3) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Plan Shares Available for Grant
Balance at the beginning of the period (in shares)	95,968	99,685
Reserved (in shares)	650,000	250,000
Stock awards granted (in shares)	(29,701)	(39,032)
Restricted stock units granted (in shares)	(25,000)
Balance at the end of the period (in shares)	307,767	95,968
Stock Options
Plan Shares Available for Grant
Available for grant (in shares)	(426,000)	(115,000)
Plan Options Outstanding
Balance at the beginning of the period (in shares)	1,251,442	1,469,673
Units Granted (in shares)	426,000	115,000
Exercised (in shares)	(155,407)	(38,165)
Balance at the end of the period (in shares)	1,255,077	1,251,442
Weighted Average Exercise Price Per Share
Balance at the beginning of the period (in dollars per share)	2.72	3.03
Granted (in dollars per share)	3.02	2.49
Exercised (in dollars per share)	1.94	1.84
Balance at the end of the period (in dollars per share)	2.86	2.72
Aggregate Intrinsic Value, Exercised (in dollars)	217,694	20,810
2003 Plan \| Stock Options
Plan Shares Available for Grant
Available for grant cancelled or forfeited (in shares)		(99,685)
Plan Options Outstanding
Cancelled or forfeited (in shares)	(224,458)	(263,666)
Weighted Average Exercise Price Per Share
Cancelled (in dollars per share)	2.95	3.64
1990 Plan \| Stock Options
Plan Options Outstanding
Cancelled or forfeited (in shares)		(31,400)
Weighted Average Exercise Price Per Share
Cancelled (in dollars per share)		10.37
2013 Plan
Plan Shares Available for Grant
Stock awards granted (in shares)	(29,701)	(39,032)
2013 Plan \| Stock Options
Plan Shares Available for Grant
Available for grant cancelled or forfeited (in shares)	42,500
Plan Options Outstanding
Cancelled or forfeited (in shares)	(42,500)
Weighted Average Exercise Price Per Share
Cancelled (in dollars per share)	3.03

Gross number of share options (or share units) available for grant during the period.

No definition available.

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- Definition

For presentations that combine terminations, the number of available shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

No definition available.

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Represents the number of stock awards granted during the period under the plan.

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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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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No definition available.

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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.

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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

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- Definition

For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)-(4)

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Weighted average price of options that were either forfeited or expired.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

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-Paragraph 2

-Subparagraph (c)(1)(iv)(3)-(4)

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- Definition

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

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No definition available.

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

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ 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)

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

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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