Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Operating activities:
Net income (loss)	$ 23,498	$ (14,115)
Non-cash elements included in net income (loss):
Depreciation, depletion and amortization	56,968	52,966
(Gain) loss on investments	(439)	3,043
(Gain) loss on disposition of properties, plants, equipment, and mineral interests	(311)	190
Provision for reclamation and closure costs	2,005	10,256
Stock compensation	3,467	2,261
Deferred income taxes	10,652	(705)
Amortization of loan origination fees	926	910
Loss on derivative contracts	5,419	7,812
Foreign exchange loss (gain)	9,721	(9,672)
Other non-cash charges, net	17	25
Change in assets and liabilities, net of business acquired:
Accounts receivable	(15,910)	2,469
Inventories	(5,802)	(3,417)
Other current and non-current assets	268	(3,904)
Accounts payable and accrued liabilities	(3,820)	(4,210)
Accrued payroll and related benefits	3,135	803
Accrued taxes	(4,591)	(1,938)
Accrued reclamation and closure costs and other non-current liabilities	935	9,399
Cash provided by operating activities	86,138	52,173
Investing activities:
Additions to properties, plants, equipment and mineral interests	(76,960)	(58,272)
Acquisition of Revett, net of cash acquired		(809)
Proceeds from disposition of properties, plants and equipment	317	153
Purchases of investments	(16,088)	(947)
Maturities of investments	840
Changes in restricted cash and investment balances	(3,900)
Net cash used in investing activities	(95,791)	(59,875)
Financing activities:
Proceeds from sale of common stock, net of offering costs	8,121
Acquisition of treasury shares	(3,384)	(941)
Dividends paid to common shareholders	(1,914)	(1,850)
Dividends paid to preferred shareholders	(276)	(276)
Credit availability and debt issuance fees paid	(83)	(123)
Repayments of debt	(1,339)
Repayments of capital leases	(4,356)	(4,940)
Net cash used in financing activities	(3,231)	(8,130)
Effect of exchange rates on cash	1,288	(2,259)
Net decrease in cash and cash equivalents	(11,596)	(18,091)
Cash and cash equivalents at beginning of period	155,209	209,665
Cash and cash equivalents at end of period	143,613	191,574
Significant non-cash investing and financing activities:
Addition of capital lease obligations	1,631	2,369
Common stock issued for the acquisition of Revett		19,133
Payment of accrued compensation in stock	$ 5,511	$ 3,016