XML 56 R40.htm IDEA: XBRL DOCUMENT v3.19.2
Note 4 - Accounts Receivable (Details Textual) - USD ($)
6 Months Ended 12 Months Ended
Jun. 30, 2019
Dec. 31, 2018
Accounts Receivable, Allowance for Credit Loss, Noncurrent $ 1,720,000 $ 1,720,000
Percentage of Remaining Balance Owned Reserved 100.00% 100.00%