Note 9 - Income Taxes  | 
6 Months Ended | 
|---|---|
Mar. 31, 2018  | |
| Notes to Financial Statements | |
| Income Tax Disclosure [Text Block] | 
 Note  9.  Income TaxesFor the  The Tax Cut and Jobs Act of three  and six  months ended  March 31, 2018,  the Company recorded a benefit for income taxes of $101,000  and $304,000,  respectively, reflecting an effective tax rate of 24.9%  and negative 91.1%,  respectively. 2017  (the “Tax Reform Act”) was enacted on  December  
22,  2017.  The Tax Reform Act reduced certain federal corporate income tax rates effective  January 1, 2018  and changed certain other provisions. The effective tax rate for the six  months ended  March 31, 2018  is a blended rate reflecting the anticipated benefit of three  quarters of federal tax rate reductions for fiscal 2018.  Our six  months tax benefit reflects a lower tax rate and a one -time benefit of $384,000  related to the favorable impact of a revaluation of our net deferred tax liability that decreased the income tax provision for the six  months ended  March 31, 2018  and reduced long-term deferred tax liabilities during the six  months ended  March 31, 2018.  The final impact of the Tax Reform Act  may  differ due to and among other things, changes in interpretations, assumptions made by the Company, the issuance of additional guidance, and actions the Company  may  take as a result of the Tax Reform Act. Additionally, differences between the effective tax rate and the statutory tax rate are related to nondeductible meals and entertainment, expenses related to equity award compensation,  favorable domestic manufacturing deduction and research and development credits.For the   three  and six  months ended  March 31, 2017,  the Company recorded a provision for income taxes of $433,000  and $800,000,  respectively, reflecting an effective tax rate of 32.3%  and 31.0%,  respectively. The primary difference between the effective tax rate and the statutory tax rate is related to nondeductible meals and entertainment, favorable domestic manufacturing deduction and research and development credits, expenses related to equity award compensation and favorable discrete items for the three  and six  months ended  March 31, 2017  from tax benefits related to stock-based compensation awards.As of    March 31, 2018  and  September 30, 2017,  the Company had a remaining valuation allowance of approximately $191,000  and $159,000,  respectively, related to state net operating loss carry forwards the Company does not  expect to utilize. As a result of recording the impact of the Tax Reform Act on its deferred assets and liabilities, the Company recorded an increase in its valuation allowance against state net operating losses carried forward of approximately $32,000  in the six  months ended  March 31, 2018.  Based on the Company’s analysis and review of long-term forecasts and all available evidence, the Company determined that there should be no  further change in the valuation allowance for the quarter ended  March 31, 2018. 
Deferred taxes recognize the impact of temporary differences between the amounts of the assets and liabilities recorded for financial statement purposes and these amounts measured in accordance with tax laws. The Company’s realization of deferred tax temporary differences is contingent upon future taxable earnings. The Company reviewed its deferred tax assets for expected utilization using a “more likely than   not”  criteria by assessing the available positive and negative factors surrounding its recoverability.As of  d tax benefits as a component of income tax expense. The Company does  March 31, 2018,  we do not  have any unrecognized tax benefits. It is the Company’s practice to recognize interest and penalties accrued on any unrecognizenot  expect any material changes in its unrecognized tax positions over the next 12  months.We are currently under examination by the U.S. Internal Revenue Service for fiscal year  
2016.  We are not  under examination by any other taxing jurisdiction. In the event of any future tax assessments, we have elected to record the income taxes and any related interest and penalties as income tax expense on our Statements of Operations. |