CONCENTRATIONS - Summary of major suppliers and customers (Details)	12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Subcontractors | Supplier Concentration Risk | Company A
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	100.00%
Accounts Payable | Supplier Concentration Risk | Company A
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company M | Sales | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company M | Accounts Receivable | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company N | Sales | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company N | Accounts Receivable | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company O | Sales | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	100.00%
Company O | Accounts Receivable | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company P | Sales | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%
Company P | Accounts Receivable | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk, percentage	0.00%	0.00%