INVESTMENTS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Mar. 29, 2019	Dec. 20, 2018	Dec. 19, 2017
Investments rollforward
Opening balance	$ 3,131	$ 7,971	$ 7,971
Additions during the period	264
Net gains (loss) on securities sold		(734)
Disposals during the period		(2,663)
Unrealized gains (loss) on securities held	827	(2,001)
Fair Value end of the period	4,222	2,573	3,131
Cumulative effect of new accounting principle	100
Proceeds from sale of investments		2,663
Cost of purchase of marketable equity securities	3,100		2,900
Price per unit				$ 1.55
Flow Through Common Shares
Investments rollforward
Price per unit					$ 2.24	$ 2.50
Marketable equity securities
Investments rollforward
Opening balance	2,718	6,404	6,404
Additions during the period	264
Net gains (loss) on securities sold		(734)
Disposals during the period		(2,663)
Unrealized gains (loss) on securities held	605	(1,137)
Fair Value end of the period	3,587	1,870	2,718
Warrants
Investments rollforward
Opening balance	413	1,567	1,567
Unrealized gains (loss) on securities held	222	(864)
Fair Value end of the period	$ 635	$ 703	$ 413