Stock Option Plans (Details Narrative) - USD ($)

12 Months Ended

Dec. 31, 2015

Dec. 31, 2014

Shares available for grant

201,350

36,475

Weighted average remaining contractual term

6 years

Stock-based compensation

$ 513,986

$ 561,856

Unrecognized compensation cost

$ 701,057

Unrecognized compensation cost recognition period

3 years

Weighted average fair value at the date of grant

$ 3.44

$ 3.27

Aggregate intrinsic value of outstanding options

$ 6,239,715

Aggregate intrinsic value of exercisable options

5,543,783

Aggregate intrinsic value of options exercised

$ 8,630,045

Employee Plan

Vesting term

Options granted under the 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

199,850

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

1,500

Shares authorized under plan

180,000

Shares offered under initial option

5,000

Shares offered under annual option

5,000