CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($)
3 Months Ended 9 Months Ended
Apr. 30, 2018
Apr. 30, 2017
Apr. 30, 2018
Apr. 30, 2017
Statement of Comprehensive Income [Abstract]        
Unrealized holding gains arising during the period, tax $ (27,037) $ 33,500 $ 43,963 $ 40,000
Reclassification adjustment for net gains included in net income, tax $ (7,770) $ (14,500) $ (7,963) $ (14,000)