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CAPITAL STOCK - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Aug. 14, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2019	Sep. 20, 2016
Class of Warrant or Right [Line Items]
Number of warrants issued (in shares)					2,328,925
Nichols Ranch, Hank and Doughstick Properties
Class of Warrant or Right [Line Items]
Number of shares issued for acquisition (in shares)	1,100,000
Total purchase price	$ 3,740
At The Market Sale Of Stock
Class of Warrant or Right [Line Items]
Sale of Stock, Number of Shares Issued in Transaction		8,043,365	14,283,254	7,202,479
Sale of stock consideration received		$ 19,680	$ 31,520	$ 14,150
Public Offerings
Class of Warrant or Right [Line Items]
Sale of Stock, Number of Shares Issued in Transaction		3,199,866	7,576,288	3,822,561
Exercise price of warrants (in dollars per share)						$ 2.45

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