Note D - Income Taxes - Income Tax Expense (Benefit) Components (Details) - USD ($)  | 
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2016  | 
Sep. 30, 2015  | 
Sep. 30, 2014  | 
|
| Current: | |||
| Federal | $ 428,638 | $ 67,373 | $ 115,049 | 
| State | 106,623 | 65,820 | 46,303 | 
| 535,261 | 133,193 | 161,352 | |
| Deferred: | |||
| Federal | 2,434,294 | 2,377,590 | 2,903,110 | 
| State | (93,523) | (35,545) | 116,516 | 
| 2,340,771 | 2,342,045 | 3,019,626 | |
| Income tax expense | $ 2,876,032 | $ 2,475,238 | $ 3,180,978 | 
| X | ||||||||||
- References No definition available. 
  | 
| X | ||||||||||
- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- Definition Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- Definition Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- References No definition available. 
  | 
| X | ||||||||||
- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- Definition Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  | 
| X | ||||||||||
- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
  |