Stock-Based Compensation - Schedule of Company's Stock Option Plans (Detail) (USD $)	9 Months Ended
Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Options outstanding, beginning of year	29,000
Number of Options, Granted
Number of Options, Exercised
Number of Options, Forfeited
Number of Options, Options outstanding, end of year	29,000
Number of Options, Options exercisable, end of year	25,000
Weighted Average Exercise Price, Options outstanding, beginning of year	$ 17.03
Weighted Average Exercise Price, Granted
Weighted Average Exercise Price, Exercised
Weighted Average Exercise Price, Forfeited
Weighted Average Exercise Price, Options outstanding, end of period	$ 17.03
Weighted Average Exercise Price, Options exercisable, end of period	$ 18.71

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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.

+ References

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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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- Definition

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.

+ References

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

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- Definition

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

+ References

No definition available.

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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 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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No definition available.

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

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