XML 31 R21.htm IDEA: XBRL DOCUMENT v3.21.2
Note 2 - Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($)
12 Months Ended
Sep. 30, 2021
Sep. 30, 2020
Allowance for doubtful accounts $ 250,000 $ 200,000
Additions Charged to Costs and Expenses (3,000) 116,000
Accounts Charged off less Recoveries 3,000 (66,000)
Allowance for doubtful accounts $ 250,000 $ 250,000