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Share-based compensation arrangement by share-based payment award options vested grant date fair value.

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Share-based compensation arrangement by share-based payment award percentage of options exercisable.

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Share-based compensation arrangement by share based payment award realized value of option exercised.

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Share Based Compensation Arrangement By Share Based Payment Awards, Options, Exercises During The Period, Net

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Shares Issued During Period Market Price Per Share

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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

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Weighted average remaining contractual term for fully vested and expected to vest options that are 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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise prices of fully vested and expected to vest options outstanding.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share instruments newly issued under a share-based compensation plan.

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

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Equity And Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
Equity And Stock-Based Compensation [Line Items]
Grant date fair value of options vesting	$ 77,000	$ 89,000	$ 130,000	$ 169,000
Unrecognized estimated compensation cost related to non-vested stock options granted	241,000		241,000
Recognition period of unrecognized compensation cost			2 years 1 month 28 days
Options exercised			50,000	95,000
Realized value of option exercised			99,500	136,000
Cash received from exercise of stock options			200,500	308,000
Intrinsic unrealized value of all options outstanding, vested and expected to vest	372,000		372,000
Percentage of option currently exercisable			92.80%
Expiration period for stock options			10 years
Common Stock authorized for issuance under 2010 Stock Incentive Plan	1,250,000		1,250,000
Weighted average remaining contractual life of all options outstanding, vested, and expected to vest			5 years 2 months 9 days		5 years 3 months 26 days
Weighted average remaining contractual life of the exercisable options outstanding			3 years 11 months 27 days		4 years 3 months 11 days
Class A [Member]
Equity And Stock-Based Compensation [Line Items]
Stocks granted			217,890	155,925
Compensation expense	188,000	238,000	376,000	476,000
Options granted			50,000	40,000	206,000
Options exercised			125,000		136,000
Class B [Member]
Equity And Stock-Based Compensation [Line Items]
Options granted
Incremental Shares Issued [Member]
Equity And Stock-Based Compensation [Line Items]
Options exercised			75,000
Realized value of option exercised			$ 124,000
In the money shares exercise of options, net			53,136
Market price per share			$ 5.66
Exercise price per share			$ 4.01
Minimum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options			0 years
Maximum [Member]
Equity And Stock-Based Compensation [Line Items]
Vesting period of stock options			4 years