Organization And Summary Of Significant Accounting Policies (Schedule Of Changes In Reserve) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Organization And Summary Of Significant Accounting Policies Schedule Of Changes In Reserve
Balance at beginning of the year	$ 263,092	$ 364,894
Accrued allowances		89,666
Reclassification of allowance from accounts receivable to accounts payable and accrued liabilities	173,426
Expenditures	12,564	191,468
Balance at year-end	$ 77,102	$ 263,092