Fair Value Measurements - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Assets:
Fair value measurements of assets	$ 83,602,865
Corporate Bonds | Fair Value, Measurements, Recurring
Assets:
Fair value measurements of assets	82,603,595	$ 8,258,982
Corporate Bonds | Fair Value, Measurements, Recurring | Level 2
Assets:
Fair value measurements of assets	82,603,595	8,258,982
Government Securities | Fair Value, Measurements, Recurring
Assets:
Fair value measurements of assets	999,270
Government Securities | Fair Value, Measurements, Recurring | Level 2
Assets:
Fair value measurements of assets	$ 999,270
Preferred Unit Warrant Liability | Fair Value, Measurements, Recurring
Liabilities:
Fair value measurements of liabilities		50,888
Preferred Unit Warrant Liability | Fair Value, Measurements, Recurring | Level 3
Liabilities:
Fair value measurements of liabilities		$ 50,888