Fair Value of Assets and Liabilities - Schedule of Warrant Liability Using Black-Scholes Option-Pricing Model (Details) - Valuation Technique, Option Pricing Model [Member] - Warrant Liability [Member] - $ / shares |
6 Months Ended | 12 Months Ended |
|---|---|---|
Jun. 30, 2018 |
Dec. 31, 2017 |
|
| Fair Value of Series A Convertible Redeemable Preferred Stock [Member] | ||
| Fair value assumptions, measurement input, per share | $ 3.55 | $ 2.93 |
| Risk Free Interest Rate [Member] | ||
| Fair value assumptions, measurement input, percentages | 2.73% | 2.26% |
| Expected Dividend Yield [Member] | ||
| Fair value assumptions, measurement input, percentages | 0.00% | 0.00% |
| Contractual Term (In Years) [Member] | ||
| Fair value assumptions, measurement input, term | 5 years 9 months 18 days | 6 years 3 months 19 days |
| Expected Volatility [Member] | ||
| Fair value assumptions, measurement input, percentages | 62.00% | 59.00% |