Note 11 - Capital Stock - Continuity Schedule of Outstanding Share Purchase Warrants (Details) - $ / shares	3 Months Ended	9 Months Ended
	Apr. 30, 2019	Apr. 30, 2019
Balance, July 31, 2018 (in shares)		30,923,489
Balance, July 31, 2018 (in dollars per share)		$ 1.97
Issued (in shares)		7,063,253
Issued (in dollars per share)		$ 2.05
Exercised (in shares)		(3,999,881)
Exercised (in dollars per share)		$ 1.21
Expired (in shares)		(3,542,951)
Expired (in dollars per share)		$ 2.13
Cancelled (in shares)		(11,000,000)
Cancelled (in dollars per share)	$ 2.30	$ 2.30
Balance, April 30, 2019 (in shares)	19,443,910	19,443,910
Balance, April 30, 2019 (in dollars per share)	$ 1.94	$ 1.94