Impairment of Long Lived Assets (Tables)

12 Months Ended

Dec. 31, 2016

Mineral Properties Asset Group

Impairment of Long Lived Assets

Schedule of details of components of the impairment of long lived assets

	Net Book Value				Net Book Value
	Prior to		Sept. 30, 2015		After
	Impairment at		Impairment		Impairment at
	Sept. 30, 2015		Charges		Sept. 30, 2015
	(in thousands)
Mineral and exploration properties	$	13,660	$	12,306	$	1,354
Exploration properties		458		458		—
Buildings, plant and equipment		3,236		—		3,236
Asset retirement cost		417		417		—
Other working capital, net		(872)		—		(872)
	$	16,899	$	13,181	$	3,718