SHAREHOLDERS' EQUITY (Details) - USD ($)								3 Months Ended
	Feb. 09, 2021	Jan. 29, 2021	Dec. 31, 2020	Sep. 10, 2020	Nov. 20, 2019	May 23, 2019	Mar. 29, 2019	Mar. 31, 2021	Jun. 30, 2020
Number of units issued						1,935,484
Net proceeds						$ 2,600,000		$ 29,875,000
Issuance costs						$ 400,000
Sale of common stock for cash, net of issuance costs								29,875,000
November 2019 Offering
Number of units issued					37,750,000
Price per unit					$ 1.325
Gross proceeds					$ 46,600,000
Net proceeds					$ 46,600,000
Warrant expiration term					5 years
Issuance costs					$ 3,500,000
Outstanding warrants								21,706,250
Warrants issued in connection with equity issuance					2,831,250
June 2020 Amended and Restated Credit Agreement
Number of units issued									2,091,700
Net proceeds									$ 1,900,000
March 2019 Offering
Number of units issued							14,193,548
Price per unit							$ 1.55
Net proceeds							$ 20,300,000
Number of shares of common stock							1
Number of warrants received for each share of common stock share sold							0.50
Issuance costs							$ 1,700,000
Outstanding warrants								8,064,516
Canadian Exploration Expenditures
Gross proceeds								$ 20,200,000
Equity Financing In February 2021
Number of units issued	30,000,000
Price per unit	$ 1.05
Gross proceeds	$ 31,500,000
Net proceeds	29,900,000
Issuance costs	$ 1,700,000
Subscription Receipts | Officers Directors And Certain Employees
Number of units issued							1,935,484
Price per unit							$ 1.55
Common Stock and Additional Paid-in Capital
Number of units issued								30,000,000
Net proceeds								$ 29,875,000
Common Stock and Additional Paid-in Capital | November 2019 Offering
Net proceeds					37,300,000
Warrant at First Stock Price | November 2019 Offering
Net proceeds					$ 9,300,000
Number of shares of common stock					1
Number of warrants received for each share of common stock share sold					0.50
Warrant at First Stock Price | March 2019 Offering
Number of shares of common stock							1
Price per common share for each warrant							$ 2.00
Warrant expiration term							3 years
Warrant at Second Stock Price | November 2019 Offering
Number of shares of common stock					1
Price per common share for each warrant					$ 1.7225
Flow Through Common Shares | Canadian Development Expenses
Number of units issued		12,600,600
Price per unit		$ 1.01
Gross proceeds		$ 12,700,000
Net proceeds		12,000,000.0
Issuance costs		700,000
Net proceeds allocated to the sale of tax benefits		1,200,000
Sale of common stock for cash, net of issuance costs		$ 10,800,000
Exploration expenditures								7,900,000
Flow Through Common Shares | Canadian Exploration Expenditures
Number of units issued			7,669,900	6,298,166
Price per unit			$ 1.28	$ 1.65
Gross proceeds			$ 9,800,000	$ 10,400,000
Net proceeds			9,800,000	9,800,000
Issuance costs			0	600,000
Net proceeds allocated to the sale of tax benefits			2,100,000	2,000,000.0
Sale of common stock for cash, net of issuance costs			$ 7,700,000	$ 7,800,000
Exploration expenditures								$ 4,300,000