Subsequent events (Detail Textuals) - USD ($)				12 Months Ended
	Oct. 04, 2019	Jul. 05, 2019	Jul. 01, 2019	Jun. 30, 2019	Jun. 30, 2018
Subsequent Event [Line Items]
Issuance of common stock for cash				$ 1,678,000	$ 16,362,000
Issuance of common stock for cash (in shares)				1,707,000	30,303,000
Conversion of notes payable to common stock				$ 232,000	$ 311,000
Conversion of notes payable to common stock (in shares)				1,449,000	2,768,000
Subsequent Event
Subsequent Event [Line Items]
Issuance of common stock for cash			$ 75,000
Issuance of common stock for cash (in shares)			115,385
Cashless exercise of stock options (in shares)			446,352
Conversion of notes payable to common stock		$ 25,000
Conversion of notes payable to common stock (in shares)		50,000
Conversion price at which notes are converted into common stock		$ 0.50
Refund amount for agreement termination			$ 808,000
Subsequent Event | Stock options | CEO
Subsequent Event [Line Items]
Number of stock options granted	9,500,000
Number of stock options vested	2,500,000