Mineral properties, plant and equipment and exploration and evaluation assets (Tables)

12 Months Ended

Dec. 31, 2018

Statements [Line Items]

Disclosure of detailed information about mineral properties [Table Text Block]

	Mineral interests
			Non-		Exploration and		Plant, buildings		Assets under		Corporate
	Depletable		depletable		evaluation		and equipment		construction		assets		Total
					assets
	$		$		$		$		$		$		$
Cost:
As at December 31, 2016	146,145		89,089		12,757		340,962		7,341		723		597,017
Additions	73,486		6,244		328		7,032		39,274		23		126,387
Changes in rehabilitiation provision	4,970		(204	)	-		-		-		-		4,766
Reclassification of VAT recoverable	2,629		-		-		-		-		-		2,629
Transfers	17,127		(16,592	)	-		18,677		(19,212	)	-		-
As at December 31, 2017	244,357		78,537		13,085		366,671		27,403		746		730,799
Additions	45,497		141		-		2,264		9,084		21		57,007
Changes in rehabilitation provision	556		(558	)	-		-		-		-		(2	)
Transfers	11,069		(5,959	)	-		20,949		(26,059	)	-		-
	301,479		72,161		13,085		389,884		10,428		767		787,804
Less: Assets of the AGM (note 6)	(301,479	)	(72,161	)	(13,085	)	(389,884	)	(10,428	)	(318	)	(787,355	)
As at December 31, 2018	-		-		-		-		-		449		449
Accumulated depreciation and depletion:
As at December 31, 2016	(23,405	)	-		-		(31,793	)	-		(575	)	(55,773	)
Depreciation and depletion	(42,354	)	-		-		(21,808	)	-		(41	)	(64,203	)
As at December 31, 2017	(65,759	)	-		-		(53,601	)	-		(616	)	(119,976	)
Depreciation and depletion	(34,395	)	-		-		(17,200	)	-		(44	)	(51,639	)
Loss associated with loss of control (note 6)	(64,537	)	(30,911	)	(3,417	)	(83,807	)	(2,539	)	-		(185,211	)
	(164,691	)	(30,911	)	(3,417	)	(154,608	)	(2,539	)	(660	)	(356,826	)
Less: Assets of the AGM (note 6)	164,691		30,911		3,417		154,608		2,539		325		356,491
As at December 31, 2018	-		-		-		-		-		(335	)	(335	)
Net book value:
As at December 31, 2017	178,598		78,537		13,085		313,070		27,403		130		610,823
As at December 31, 2018	-		-		-		-		-		114		114