Stockholders' Equity - Schedule of Non-qualified Stock Options (Details) - Non-Qualified Stock Option [Member] - $ / shares	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Number of Stock Options, Options outstanding, beginning of year	164,167	234,167
Number of Stock Options, Granted
Number of Stock Options, Redeemed	(8,750)	(3,750)
Number of Stock Options, Exercised	(2,500)	(7,500)
Number of Stock Options, Expired / terminated
Number of Stock Options, Options outstanding, end of year	152,917	222,917
Number of Stock Options, Options exercisable, end of year	152,917	222,917
Weighted Exercise Price, Option outstanding, beginning of year	$ 3.13	$ 2.47
Weighted Exercise Price, Granted
Weighted Exercise Price, Redeemed	1.45	0.84
Weighted Exercise Price, Exercised	1.45	0.84
Weighted Exercise Price, Expired / terminated
Weighted Exercise Price, Option outstanding end of quarter	3.25	2.55
Weighted Exercise Price, Options exercisable, end of quarter	$ 3.25	$ 2.55

Number of options, redeemed.

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Weighted average exercise price, redeemed.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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