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Stockholders' Equity - Additional Information (Details) - USD ($) |  |  |  |  | 1 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Feb. 09, 2018 | Feb. 05, 2018 | Dec. 13, 2017 | Oct. 10, 2017 | Dec. 31, 2015 | Dec. 31, 2011 | Nov. 30, 2008 | Jun. 30, 2018 | Feb. 01, 2018 | Dec. 31, 2017 | Dec. 18, 2017
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized |  |  | 5,000,000 |  |  |  |  | 10,000,000 |  |  |
Common stock, shares authorized |  |  | 11,000,000 |  |  |  |  | 50,000,000 |  | 50,000,000 |
Common stock, par value |  |  |  |  |  |  |  | $ 0.0001 |  | $ 0.0001 |
Preferred stock, conversion basis |  |  |  |  |  |  |  | one-for-one basis |  |  |
Common stock voting rights |  |  |  |  |  |  |  | one vote for each share |  |  |
Common stock, shares issued |  |  |  |  |  |  |  | 12,779,210 |  | 5,514,917 |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  | $ 19,500,000 |  |  |
Warrants to purchase common stock |  |  |  |  |  |  |  |  | 380,000 |  |
Warrants exercise price |  |  |  |  |  |  |  |  | $ 6.00 |  |
Fair value of warrants |  |  |  |  |  |  |  | 669,408 |  |  |
Exercise of stock options |  |  |  |  |  |  |  | $ 59,150 |  |  |
Preferred stock, shares outstanding |  |  |  |  |  |  |  |  | 0 |  |
Description of preferred shares convertible terms |  |  |  |  |  |  |  | Series A Preferred Stock, Series B Preferred Stock, and Series C Preferred Stock (“Preferred Shares”) were convertible at any time at the option of the holder into one share of common stock. |  |  |
Preferred stock, no par value |  |  |  |  |  |  |  |  |  |  |
Weighted-average grant date fair value of common stock options issued |  |  |  |  |  |  |  | 0 |  |  |
Unvested common stock options, net of estimated forfeitures |  |  |  |  |  |  |  | $ 182,409 |  |  |
Unearned stock-based compensation expected to be recognized |  |  |  |  |  |  |  | 10 months 28 days |  |  |
Maximum |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Ownership interest percentage |  |  |  |  |  |  |  | 10.00% |  |  |
Options expiration period date of grant |  |  |  |  |  |  |  | 10 years |  |  |
Minimum |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Proceeds from convertible preferred stock to common stock |  |  | $ 10,000,000 |  |  |  |  |  |  |  |
Preferred stock, par value |  |  | $ 5.00 |  |  |  |  |  |  |  |
Fair market value of common stock on date of grant |  |  |  |  |  |  |  | 110.00% |  |  |
Options expiration period date of grant |  |  |  |  |  |  |  | 5 years |  |  |
Cashless Exercise of Stock Options |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of common stock issued |  |  |  |  |  |  |  | 265,366 |  |  |
Restricted Stock Units (RSUs) |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Unvested common stock options, net of estimated forfeitures |  |  |  |  |  |  |  | $ 522,417 |  |  |
Unearned stock-based compensation expected to be recognized |  |  |  |  |  |  |  | 1 year 21 days |  |  |
Stock option vested during period |  |  |  |  |  |  |  | 0 |  |  |
Number of Shares, Warrants granted |  |  |  |  |  |  |  | 160,000 |  |  |
Stock Options |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of common stock issued |  |  |  |  |  |  |  | 327,287 |  |  |
Exercise of stock options |  |  |  |  |  |  |  | $ 59,150 |  |  |
Common Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of common stock issued |  |  |  |  |  |  |  | 327,287 |  |  |
Exercise of stock options |  |  |  |  |  |  |  | $ 33 |  |  |
Common Stock | Maximum | 2017 Equity Incentive Plan |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  |  |  |  |  |  | 1,500,000
Common Stock | 2000 Plan |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares granted |  |  |  |  |  |  | 3,000,000 |  |  |  |
Common Stock | 2011 Plan |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares available for grant |  |  |  |  |  |  |  |  |  | 240,000 |
Common Stock | 2011 Plan | Maximum |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares granted |  |  |  |  |  | 1,500,000 |  |  |  |  |
Common Stock | 2015 Plan |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares available for grant |  |  |  |  |  |  |  |  |  | 790,000 |
Common Stock | 2015 Plan | Maximum |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of shares granted |  |  |  |  | 1,500,000 |  |  |  |  |  |
Common Stock | Board of Directors | 2011 Plan |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares available for grant |  |  |  | 0 |  |  |  |  |  |  |
Stock options, termination date |  |  |  | Oct. 10, 2017 |  |  |  |  |  |  |
Common Stock | Board of Directors | 2015 Plan |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Shares available for grant |  |  |  | 0 |  |  |  |  |  |  |
Stock options, termination date |  |  |  | Oct. 10, 2017 |  |  |  |  |  |  |
Warrants |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Warrants exercise price |  |  |  |  |  |  |  | $ 5.00 |  |  |
Fair value of warrants |  |  |  |  |  |  |  | $ 699,408 |  |  |
Fair value assumptions, contractual term |  |  |  |  |  |  |  | 5 years |  |  |
Fair value assumptions, volatility rate |  |  |  |  |  |  |  | 42.70% |  |  |
Fair value assumptions, dividend rate |  |  |  |  |  |  |  | 0.00% |  |  |
Fair value assumptions, risk-free interest rate |  |  |  |  |  |  |  | 2.72% |  |  |
Number of Shares, Warrants granted |  |  |  |  |  |  |  | 380,000 |  |  |
Initial Public Offering |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Number of Shares, Warrants granted |  |  |  |  |  |  |  | 380,000 |  |  |
Initial Public Offering | Common Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common stock, par value |  |  |  |  |  |  |  |  |  |  | $ 0.0001
Common stock, shares issued |  | 3,800,000 |  |  |  |  |  |  |  |  |
Common stock price |  | $ 5.00 |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  | $ 19,000,000 |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock |  | 17,485,000 |  |  |  |  |  |  |  |  |
Underwriting discounts and commissions |  | 1,330,000 |  |  |  |  |  |  |  |  |
Underwriter offering-related transaction costs |  | 185,000 |  |  |  |  |  |  |  |  |
Accounting, legal and other fees and costs |  | 1,148,352 |  |  |  |  |  |  |  |  |
Warrant expense |  | $ 699,408 |  |  |  |  |  |  |  |  |
Over-allotment Option | Common Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common stock, shares issued | 200,000 |  |  |  |  |  |  |  |  |  |
Common stock price | $ 5.00 |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock | $ 500,000 |  |  |  |  |  |  |  |  |  |
Net proceeds from issuance of common stock | 465,000 |  |  |  |  |  |  |  |  |  |
Underwriting discounts and commissions | $ 35,000 |  |  |  |  |  |  |  |  |  |
Over-allotment Option | Common Stock | Under Writers |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Over allotment option to purchase additional shares | 100,000 |  |  |  |  |  |  |  |  |  |
Over-allotment Option | Common Stock | CEO’s Family Trust |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Over allotment option to purchase additional shares | 100,000 |  |  |  |  |  |  |  |  |  |
Series A Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized |  |  | 500,000 |  |  |  |  |  |  | 500,000 |
Common stock, par value |  |  |  |  |  |  |  |  | $ 0.0001 |  |
Preferred stock, shares outstanding |  |  |  |  |  |  |  | 0 |  | 500,000 |
Preferred stock, liquidation preference per share |  |  | $ 0.25 |  |  |  |  |  |  | $ 125,000 |
Preferred stock, no par value |  |  |  |  |  |  |  |  |  |  |
Series B Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized |  |  | 1,500,000 |  |  |  |  |  |  | 1,500,000 |
Common stock, par value |  |  |  |  |  |  |  |  | 0.0001 |  |
Preferred stock, shares outstanding |  |  |  |  |  |  |  | 0 |  | 1,450,000 |
Preferred stock, liquidation preference per share |  |  | $ 0.50 |  |  |  |  |  |  | $ 725,000 |
Preferred stock, no par value |  |  |  |  |  |  |  |  |  |  |
Series C Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized |  |  | 2,000,000 |  |  |  |  |  |  | 2,000,000 |
Common stock, par value |  |  |  |  |  |  |  |  | $ 0.0001 |  |
Preferred stock, shares outstanding |  |  |  |  |  |  |  | 0 |  | 1,087,006 |
Preferred stock, liquidation preference per share |  |  | $ 1.50 |  |  |  |  |  |  | $ 1,630,508 |
Preferred stock, no par value |  |  |  |  |  |  |  |  |  |  |
Series A, Series B, and Series C, Preferred Stock |  |  |  |  |  |  |  |  |  |  |
Class Of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |
Stock split, conversion ratio |  |  |  |  |  |  |  |  | 1 |  |

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