Stock Option Plans (Details Narrative) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Shares available for grant	85,000	62,700
Weighted average remaining contractual term	6 years
Stock-based compensation	$ 869,055	$ 684,351
Unrecognized compensation cost	$ 2,151,417
Unrecognized compensation cost recognition period	3 years
Weighted average fair value at the date of grant	$ 5.77	$ 4.83
Aggregate intrinsic value of outstanding options	$ 1,566,625
Aggregate intrinsic value of exercisable options	1,566,625
Aggregate intrinsic value of options exercised	768,075
Cash settlement of stock options	$ 768,075	$ 823,530
Employee Plan
Vesting term	Options granted under the 2012 Employee Plan vest 25% one day after the first anniversary of the grant date and 25% one day after each of the next three anniversaries. Under the terms of the Employee Plan, no option may be granted under that plan after the tenth anniversary of the adoption of the plan. Options outstanding under the Company's 2002 Employee Stock Option Plan have the same vesting schedule as the 2012 Employee plan.
Shares available for grant	65,000
2005 Director Plan
Vesting term	The Initial Option vests 25% on the date of grant and 25% on the anniversary of the grant date in each of the following 3 years. Each Annual Option becomes fully exercisable one day after the date of grant. The exercise price of each option granted equals the fair market value of the Common Stock on the date the option is granted, and expires ten (10) years from the date of grant.
Shares authorized under plan	180,000
Shares offered under initial option	5,000
Shares offered under annual option	5,000
2017 Director Plan
Vesting term	The Initial Option vests 25% on the date of grant and 25% on the anniversary of the grant date in each of the following 3 years. Each Annual Option becomes fully exercisable one day after the date of grant. The exercise price of each option granted equals the fair market value of the Common Stock on the date the option is granted, and expires ten (10) years from the date of grant.
Shares available for grant	20,000
Shares authorized under plan	60,000
Shares offered under initial option	5,000
Shares offered under annual option	5,000