MINING INTERESTS (Tables)

12 Months Ended

Dec. 31, 2019

Property, plant and equipment [abstract]

Summary of the cost, accumulated depreciation and net book value of plant and equipment, mining properties and construction in progress

The following table shows the breakdown of the cost, accumulated depreciation and net book value of plant and equipment, mining properties and construction in progress:

	Plant and equipment			Mining properties		Construction in progress			Total
Cost
As of December 31, 2017	479,214			798,433		126,923			1,404,570
Additions	95			677		45,485			46,257
Transfers	16,516			127,902		(144,418		)	—
Capitalized interest	—			—		579			579
Change in rehabilitation provision estimate	—			3,218		—			3,218
Disposals and other	(17,065		)	—		—			(17,065		)
Balance at December 31, 2018	$	478,760		$	930,230	$	28,569		$	1,437,559
Additions	2,869			288		72,615			75,772
Transfers	11,586			71,337		(82,923		)	—
Change in rehabilitation provision estimate	—			4,830		—			4,830
Disposals and other	(621		)	—		—			(621		)
Balance at December 31, 2019	$	492,594		$	1,006,685	$	18,261		$	1,517,540
Accumulated depreciation
As of December 31, 2017	437,292			713,220		—			1,150,512
Depreciation and amortization	12,349			20,900		—			33,249
Disposals and other	(16,842		)	—		—			(16,842		)
Balance at December 31, 2018	$	432,799		$	734,120	$	—		$	1,166,919
Depreciation and amortization	10,582			19,044		—			29,626
Disposals and other	(456		)	—		—			(456		)
Impairment charges (see Note 19)	7,338			49,424		—			56,762
Balance at December 31, 2019	$	450,263		$	802,588	$	—		$	1,252,851
Carrying amount
Balance at December 31, 2018	$	45,961		$	196,110	$	28,569		$	270,640
Balance at December 31, 2019	$	42,331		$	204,097	$	18,261		$	264,689