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Summary of Significant Accounting Policies - Warranty Accrual (Details) - USD ($)
3 Months Ended
Jan. 31, 2020
Jan. 31, 2019
Accounting Policies [Abstract]    
Beginning balance $ 60,000 $ 80,000
Warranty service provided (22,606) (39,946)
New product warranties 14,430 16,592
Changes to pre-existing warranty accruals 8,176 13,354
Ending balance $ 60,000 $ 70,000