Valuation And Qualifying Accounts (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Allowance For Doubtful Accounts [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	$ 398,847	$ 361,350
Additions Charged to Cost and Expenses	(14,535)	64,294
Deductions	(4,100)	(26,797)
Balance at the End of Year	380,212	398,847
Inventory Valuation Reserve [Member]
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at Beginning of Year	4,460,811	3,901,772
Additions Charged to Cost and Expenses	(351,925)	320,446
Deductions	(213,435)	238,593
Balance at the End of Year	$ 3,895,451	$ 4,460,811