Stock-Based Compensation and Shareholders' Equity (Schedule of Stock Option Activity) (Details) (USD $) In Thousands, except Share data, unless otherwise specified	9 Months Ended
Sep. 30, 2012
Stock-Based Compensation And Shareholders' Equity [Abstract]
Number of options: Outstanding	156,275
Number of options: Exercicsed	(28,700)
Number of options: Forfeited	(12,050)
Number of options: Granted	20,000
Number of options: Outstanding	135,525
Number of options: Exercisable	78,625
Weighted average exercise price: Outstanding	$ 21.93
Weighted average exercise price: Exercised	$ 17.21
Weighted average exercise price: Forfeited	$ 25.15
Weighted average exercise price: Granted	$ 21.35
Weighted average exercise price: Outstanding	$ 22.55
Weighted average exercise price: Exercisable	$ 24.50
Weighted average remaining contractual term (in yrs.): Outstanding at September 30, 2012	2 years 1 month
Weighted average remaining contractual term (in yrs.): Exercisable at September 30, 2012	1 year 1 month
Aggregated intrinsic value: Outstanding	$ 559
Aggregate intrinsic value: Exercisable	$ 269

The number of shares under options that were exercised during the reporting period pertaining to the stock option plan.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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- Definition

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.

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

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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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.

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