Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements (Details)

v3.10.0.1
Fair Value Measurements (Details) - USD ($)
Sep. 30, 2018
Dec. 31, 2017
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, Fair Value Disclosure $ 237,624,503 $ 235,195,034