Stock-Based Compensation (Details 2) (USD $)	6 Months Ended	12 Months Ended
Jun. 30, 2012	Dec. 31, 2011
Schedule of Stock Options Activity
Beginning outstanding balance	3,267,838	4,000,526
Granted	303,650	429,963
Exercised	(197,652)	(560,132)
Forfeited and cancelled	(262,425)	(602,519)
Ending outstanding balance	3,111,411	3,267,838
Aggregate intrinsic value of options exercised	$ 361,000	$ 2,485,000
Weighted average fair value of options granted	$ 3.33	$ 4.07

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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-Name Accounting Standards Codification

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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.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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