| Note 4 - Stock Based Compensation (Detail) - Stock Option Activity (USD $) | 3 Months Ended | |
|---|---|---|
| Dec. 31, 2012 | Dec. 31, 2011 | |
| Outstanding at September 30, 2012 | 1,029,176 | |
| Outstanding at September 30, 2012 (in Dollars per share) | $ 3.07 | |
| Exercised | (16,037) | 74,251 | 
| Exercised (in Dollars per share) | $ 1.63 | |
| Cancelled or Forfeited | (5,500) | |
| Cancelled or Forfeited (in Dollars per share) | $ 5.33 | |
| Outstanding at December 31, 2012 | 1,007,639 | |
| Outstanding at December 31, 2012 (in Dollars per share) | $ 3.08 | |
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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. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Weighted average price of options that were either forfeited or expired. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available. 
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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