| 16. Income Taxes (Tables)
 | 12 Months Ended | 
| Sep. 30, 2018 | 
|---|
| Income Tax Disclosure [Abstract] |  | 
| Reconciliation of income tax expense | 
    |  |  | Year Ended |  |  | Year Ended |  |  
    |  |  | September 30, |  |  | September 30, |  |  
    |  |  | 2018 |  |  | 2017 |  |  
    | Current expense: |  |  |  |  |  |  |  |  |  
    | Federal |  | $ | (16,621 | ) |  | $ | 313,405 |  |  
    | State |  |  | 243,631 |  |  |  | 243,841 |  |  
    |  |  |  | 227,010 |  |  |  | 557,246 |  |  
    |  |  |  |  |  |  |  |  |  |  
    | Deferred expense: |  |  |  |  |  |  |  |  |  
    | Federal |  |  | 3,471,657 |  |  |  | 3,397,732 |  |  
    | State |  |  | 367,526 |  |  |  | 126,841 |  |  
    | Change in valuation allowance |  |  | 340,906 |  |  |  | – |  |  
    |  |  |  | 4,180,089 |  |  |  | 3,524,573 |  |  
    | Total income tax expense |  | $ | 4,407,099 |  |  |  | 4,081,819 |  |  | 
| Reconciliation between effective and statutory income tax rates | 
    |  |  | Year Ended |  |  | Year Ended |  |  
    |  |  | September 30, |  |  | September 30, |  |  
    |  |  | 2018 |  |  | 2017 |  |  
    |  |  |  |  |  |  |  |  
    | Federal statutory rates |  | $ | 2,507,740 |  |  | $ | 3,598,424 |  |  
    | State income taxes, net of federal benefit |  |  | 340,018 |  |  |  | 299,216 |  |  
    | Permanent differences |  |  | 67,579 |  |  |  | 71,908 |  |  
    | Impact of federal rate change from Tax Act |  |  | 3,037,057 |  |  |  | – |  |  
    | Bargain gain - purchase accounting |  |  | (1,455,598 | ) |  |  | – |  |  
    | Property & equipment adjustment |  |  | (273,525 | ) |  |  | – |  |  
    | Federal carryfoward attributes trued up |  |  | (170,731 | ) |  |  | – |  |  
    | Change in valuation allowance |  |  | 340,906 |  |  |  | – |  |  
    | Other |  |  | 13,653 |  |  |  | 112,271 |  |  
    | Effective rate |  | $ | 4,407,099 |  |  | $ | 4,081,819 |  |  | 
| Schedule of deferred income tax assets and liabilities | 
    |  |  | Year Ended |  |  | Year Ended |  |  
    |  |  | September 30, |  |  | September 30, |  |  
    |  |  | 2018 |  |  | 2017 |  |  
    | Deferred income tax assets (liabilities): |  |  |  |  |  |  |  |  |  
    | Allowance for bad debts |  | $ | 229,048 |  |  | $ | 401,867 |  |  
    | Accrued expenses |  |  | 22,664 |  |  |  | 31,183 |  |  
    | Inventory |  |  | (8,381 | ) |  |  | 772,656 |  |  
    | Accrued compensation |  |  | 33,670 |  |  |  | – |  |  
    | Net operating loss |  |  | 6,050,336 |  |  |  | 7,804,948 |  |  
    | Tax credits |  |  | 259,026 |  |  |  | 377,776 |  |  
    | Stock compensation |  |  | 2,252,254 |  |  |  | 2,982,009 |  |  
    | Intangibles |  |  | (1,387,115 | ) |  |  | 13,126 |  |  
    | Property & equipment |  |  | (3,890,234 | ) |  |  | (3,387,298 | ) |  
    | Other |  |  | – |  |  |  | 3,743 |  |  
    | Less: Valuation allowance |  |  | (340,906 | ) |  |  | – |  |  
    | Total deferred income tax asset |  | $ | 3,220,362 |  |  | $ | 9,000,010 |  |  |