Stock-based Compensation (Details1) (USD $)	6 Months Ended
Dec. 31, 2012
Balance, beginning	187,050
Granted
Exercised	(23,400)
Forfeited or expired	(500)
Outstanding, ending	163,150
Vested or expected to vest, end of period	155,295
Exercisable, end of period	105,200
Weight Average Exercise Price
Balance, beginning	$ 20.69
Granted
Exercised	$ 17.85
Forfeited or expired	$ 25.14
Outstanding, ending	$ 21.08
Vested or expected to vest, end of period	$ 20.87
Exercisable, end of period	$ 18.84
Weighted Average Remaining Contractual Term
Balance, beginning	6 years 11 months
Outstanding, ending	6 years 9 months
Vested or expected to vest, end of period	6 years 7 months
Exercisable, end of period	5 years 6 months
Aggregate Intrinsic Value
Outstanding end of period	$ 672,374
Vested or expected to vest, end of period	671,908
Exercisable, end of period	$ 668,927

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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

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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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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of fully vested and expected to vest options that are exercisable.

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As of the balance sheet date, the weighted-average exercise price (at which grantees can acquire the shares reserved for issuance) for exercisable stock options that are fully vested or expected to vest.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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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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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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Weighted average remaining contractual term of outstanding stock options, 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 options (or share units) exercised during the current period.

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