Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - Schedule of Fair Value of Assets on Recurring Basis (Details)

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Fair Value Measurements - Schedule of Fair Value of Assets on Recurring Basis (Details)
Apr. 30, 2018
USD ($)
Cash equivalents $ 4,800,000
Total 23,656,948
Level 1 [Member]  
Total 23,655,409
Level 2 [Member]  
Total 1,539
Level 3 [Member]  
Total
Money Market Fund [Member]  
Cash equivalents 539,796
Money Market Fund [Member] | Level 1 [Member]  
Cash equivalents 538,257
Money Market Fund [Member] | Level 2 [Member]  
Cash equivalents 1,539
Money Market Fund [Member] | Level 3 [Member]  
Cash equivalents
US Treasury Securities [Member]  
Cash equivalents 4,244,236
Held-to-maturity investments 18,872,916
US Treasury Securities [Member] | Level 1 [Member]  
Cash equivalents 4,244,236
Held-to-maturity investments 18,872,916
US Treasury Securities [Member] | Level 2 [Member]  
Cash equivalents
Held-to-maturity investments
US Treasury Securities [Member] | Level 3 [Member]  
Cash equivalents
Held-to-maturity investments