Revenue and expenses (Tables)

12 Months Ended

Dec. 31, 2017

Statement [Line Items]

Disclosure of detailed information about revenue [Table Text Block]

					Year ended
					December 31,
		2017			2016
Copper	$	925,074		$	835,470
Zinc		352,941			236,971
Gold		130,837			119,792
Silver		45,793			52,108
Other		13,974			2,719
		1,468,619			1,247,060
Treatment and refining charges		(106,066	)		(118,382	)
	$	1,362,553		$	1,128,678

Disclosure of depreciation and amortization expense [Table Text Block]

				Year ended
				December 31,
		2017		2016
Cost of sales	$	292,880	$	298,630
Selling and administrative expenses		355		504
	$	293,235	$	299,134

Disclosure of detailed information about share-based payment expenses (recoveries) [Table Text Block]

		Cash-settled				Total share-based
		RSUs		DSUs		payment expense
Year ended December 31, 2017
Cost of sales	$	1,946	$	-	$	1,946
Selling and administrative expenses		9,667		2,982		12,649
Other operating expenses		1,324		-		1,324
	$	12,937	$	2,982	$	15,919
Year ended December 31, 2016
Cost of sales	$	860	$	-	$	860
Selling and administrative expenses		6,452		2,111		8,563
Other operating expenses		464		-		464
	$	7,776	$	2,111	$	9,887

Disclosure of detailed information about employee benefits expense [Table Text Block]

		Year ended
		December 31,
		2017		2016
Current employee benefits	$	147,760	$	136,299
Profit-sharing plan expense		19,757		5,064
Share-based payments (notes 5c, 18, 23)
Cash-settled restricted share units		12,937		7,776
Cash-settled deferred share units		2,982		2,111
Employee share purchase plan		1,328		1,303
Post-employment pension benefits
Defined benefit plans		10,132		12,121
Defined contribution plans		2,443		1,061
Past service costs		10,442		-
Other post-retirement employee benefits		7,250		7,406
Termination benefits		419		1,810
	$	215,450	$	174,951

Disclosure of other operating expense [Table Text Block]

					Year ended
					December 31,
		2017			2016
Regional costs	$	4,308		$	4,388
Constancia insurance recovery		(12,857	)		-
Realized gain on contingent consideration of Balmat		(6,400	)
Other expenses		2,509			6,198
	$	(12,440	)	$	10,586

Disclosure of finance cost (income) [Table Text Block]

					Year ended
					December 31,
		2017			2016
Finance income	$	(2,849	)	$	(2,792	)
Finance expense
Interest expense on long-term debt		87,819			108,767
Accretion on financial liabilities at amortized cost		1,302			1,316
Unwinding of discounts on provisions		4,159			2,586
Tender premium on 9.50% senior unsecured notes		-			47,718
Withholding taxes		9,641			10,083
Other finance expense		13,256			11,306
		116,177			181,776
Interest capitalized		(13,149	)		(14,705	)
		103,028			167,071
Other finance losses (gains)
Net foreign exchange loss (gain)		15,772			(489	)
Change in fair value of financial assets and liabilities at fair value through profit or loss:
Hudbay warrants		(1,051	)		2,111
Embedded derivatives		1,790			(1,238	)
Investments classified as held-for-trading		(80	)		(119	)
Reclassified from other comprehensive income on disposal of available-for-sale investments		(89	)		(1,475	)
Reclassified from other comprehensive income on impairment of available-for-sale investments		2,059			1,102
		18,401			(108	)
Net finance expense	$	118,580		$	164,171

Disclosure of detailed information about impairment loss by segment [Table Text Block]

		Manitoba
Pre-tax impairment to:
Property, plant & equipment (note 11)	$	11,320
Tax impact - (recovery)		(3,849	)
After-tax impairment charge	$	7,471