Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 168,614	$ 190,984
Accounts receivable:
Trade	11,927	17,555
Other, net	8,383	7,466
Inventories:
Concentrates, doré, and stockpiled ore	19,677	15,073
Materials and supplies	14,068	13,564
Current deferred income taxes	23,043	29,398
Other current assets	12,519	8,858
Total current assets	258,231	282,898
Non-current investments	9,429	9,614
Non-current restricted cash and investments	883	871
Properties, plant, equipment and mineral interests, net	1,007,896	996,659
Non-current deferred income taxes	88,729	86,365
Other non-current assets and deferred charges	14,944	1,883
Total assets	1,380,112	1,378,290
Current liabilities:
Accounts payable and accrued liabilities	37,256	43,162
Accrued payroll and related benefits	15,806	10,760
Accrued taxes	9,824	12,321
Current portion of capital leases	7,294	5,564
Current portion of accrued reclamation and closure costs	19,845	19,845
Other current liabilities		3,335
Total current liabilities	90,025	94,987
Capital leases	15,389	11,935
Accrued reclamation and closure costs	94,056	93,370
Other non-current liabilities	37,446	40,047
Total liabilities	236,916	240,339
Commitments and contingencies (Notes 2, 4, 7, 9, 11, 13, 14)
Preferred stock, 5,000,000 shares authorized:
Series B preferred stock, $0.25 par value, 157,816 shares issued and outstanding, liquidation preference — $7,891	39	39
Common stock, $0.25 par value, 500,000,000 shares authorized; issued and outstanding 2013 — 285,163,224 shares and 2012 — 285,209,848 shares	71,500	71,499
Capital surplus	1,219,080	1,218,283
Accumulated deficit	(115,896)	(123,288)
Accumulated other comprehensive loss	(26,577)	(23,918)
Less treasury stock, at cost; 2013 - 838,288 and 2012 - 788,288	(4,950)	(4,664)
Total shareholders’ equity	1,143,196	1,137,951
Total liabilities and shareholders’ equity	$ 1,380,112	$ 1,378,290