Disclosure of Share-based Compensation Arrangements by Share-based Payment Award (Details)	6 Months Ended
	Oct. 31, 2017 USD ($)
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 1	$ 2.03
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 2	10,000
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 3	3,800
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 4	2,083
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 5	792
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 6	2.40
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 7	60,000
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 8	600
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 9	18,750
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 10	188
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 11	2.41
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 12	49,938
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 13	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 14	23,112
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 15	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 16	2.46
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 17	25,000
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 18	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 19	3,646
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 20	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 21	2.50
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 22	210,558
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 23	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 24	178,256
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 25	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 26	355,496
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 27	4,400
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 28	225,847
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 29	980
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 30	396,922
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 31	0
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 32	221,739
Common Stock Disclosure Of Share-based Compensation Arrangements By Share-based Payment Award 33	$ 0