Consolidated Balance Sheets (Parenthetical) - USD ($)	Sep. 30, 2019	Dec. 31, 2018
CURRENT ASSETS:
Allowance for doubtful accounts	$ 17,339	$ 15,703	[1]
Accumulated amortization	$ 692,869	$ 690,869	[1]
STOCKHOLDERS' EQUITY:
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10	[1]
Preferred stock, shares authorized (in shares)	20,000,000	20,000,000	[1]
Preferred stock, shares issued (in shares)	0	0	[1]
Preferred stock, shares outstanding (in shares)	0	0	[1]
Common stock, par value (in dollars per share)	$ 0.0024	$ 0.0024	[1]
Common stock, shares authorized (in shares)	25,000,000	25,000,000	[1]
Common stock, shares issued (in shares)	10,354,563	10,353,155	[1]
Treasury stock, shares (in shares)	1,424,376	1,292,594	[1]
Accumulated other comprehensive loss, tax	$ 413,019	$ 480,112

[1] As described in Note 2 to these Consolidated Financial Statements, we have restated the Consolidated Financial Statements.