Trade and other receivables (Tables)

12 Months Ended

Dec. 31, 2017

Statement [Line Items]

Disclosure of detailed information about trade and other receivables explanatory [Table Text Block]

		Dec. 31, 2017		Dec. 31, 2016
Current
Trade receivables	$	119,055	$	85,386
Embedded derivatives - provisional pricing (note 26c)		17,427		12,538
Statutory receivables		13,961		43,808
Receivable from joint venture partners		2,808		-
Other receivables		2,271		10,835
		155,522		152,567
Non-current
Taxes receivable		14,394		12,424
Receivable from joint venture partners		16,414		18,681
Other receivables		1,651		1,543
		32,459		32,648
	$	187,981	$	185,215