Accrued Expenses And Other Liabilities - Schedule of Accrued Expenses and Other Liabilities (Details) - USD ($) |
Jun. 30, 2018 |
Dec. 31, 2017 |
|---|---|---|
| Payables And Accruals [Abstract] | ||
| Accrued compensation and benefits | $ 1,526,964 | $ 1,435,015 |
| Accrued professional fees | 388,267 | 1,119,959 |
| Accrued research and development expenses | 326,401 | 182,500 |
| Accrued unvested common stock subject to repurchase | 116,801 | 122,551 |
| Accrued expenses | $ 2,358,433 | $ 2,860,025 |