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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.

+ References

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

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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.

+ References

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Aggregate unrecognized cost of share-based awards, other than options, made to employees under an equity-based compensation plan, that have yet to vest.

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No definition available.

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Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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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 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

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

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

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-Name Accounting Standards Codification

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

+ References

No definition available.

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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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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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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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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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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Note 6 - Stock-Based Compensation (Detail) (USD $)	1 Months Ended		3 Months Ended		12 Months Ended	15 Months Ended	1 Months Ended	3 Months Ended				3 Months Ended		12 Months Ended	3 Months Ended				12 Months Ended
Note 6 - Stock-Based Compensation (Detail) (USD $)	Jan. 31, 2013	May 19, 2011	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Mar. 31, 2013	Feb. 28, 2013 Restricted Stock [Member]	Mar. 31, 2013 Restricted Stock [Member]	Mar. 31, 2012 Restricted Stock [Member]	Dec. 31, 2012 Restricted Stock [Member]	Dec. 31, 2011 Restricted Stock [Member]	Mar. 31, 2013 Minimum [Member] Pay Period [Member]	Mar. 31, 2013 Minimum [Member]	Dec. 31, 2011 Minimum [Member]	Mar. 31, 2013 Minimum Hours Per Week [Member]	Mar. 31, 2013 Minimum Months Per Year [Member]	Mar. 31, 2013 Maximum [Member] Offering Period [Member]	Mar. 31, 2013 Maximum [Member] Annually [Member]	Dec. 31, 2011 Maximum [Member]	Mar. 31, 2013 Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)			1,815,000			1,815,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross (in Shares)	3,000		3,000
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	10 years		7 years 6 months		7 years 6 months									6 years					7 years 6 months
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years						4 years
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period (in Shares)							383,142	383,142	243,767
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value			$ 6,600,000			$ 6,600,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value			538,000	68,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested in Period, Fair Value			119,000			122,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Stock Options			245,000			245,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition			3 years 131 days					3 years 215 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number (in Shares)								559,192	330,572	316,686	202,555
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Share-based Awards Other than Options								11,100,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized (in Shares)		500,000
Employee Stock Purchase Plan Percentage Of Market Value			85.00%			85.00%
Share-based Compensation Arrangement by Share-based Payment Award, Award Requisite Service Period													1 year		20 hours	5 months
Amount Contributed To ESPP												10					6,250	25,000
Share-based Compensation Arrangement by Share-based Payment Award, Maximum Employee Subscription Rate																				10.00%
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant (in Shares)			454,008			454,008
Allocated Share-based Compensation Expense			$ 710,000	$ 1,186,000