Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Current assets:
Cash and cash equivalents	$ 296,375	$ 190,984
Accounts receivable:
Trade	8,306	17,555
Other, net	20,228	7,466
Inventories:
Concentrates, doré, and stockpiled ore	18,771	15,073
Materials and supplies	20,059	13,564
Current deferred income taxes	16,485	29,398
Other current assets	18,893	8,858
Total current assets	399,117	282,898
Non-current investments	8,766	9,614
Non-current restricted cash and investments	5,287	871
Properties, plants, equipment and mineral interests, net	1,742,696	996,659
Non-current deferred income taxes	99,144	86,365
Other non-current assets and deferred charges	17,445	1,883
Total assets	2,272,455	1,378,290
Current liabilities:
Accounts payable and accrued liabilities	60,864	43,162
Accrued payroll and related benefits	16,796	10,760
Accrued taxes	5,312	12,321
Current portion of capital leases	7,128	5,564
Other current liabilities	8,110	3,335
Current portion of accrued reclamation and closure costs	19,845	19,845
Total current liabilities	118,055	94,987
Capital leases	13,671	11,935
Accrued reclamation and closure costs	105,462	93,370
Long-term debt	490,104
Non-current deferred tax liability	169,030
Other noncurrent liabilities	41,407	40,047
Total liabilities	937,729	240,339
Commitments and contingencies
SHAREHOLDERS’ EQUITY
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, authorized 500,000,000 shares; issued and outstanding 2013 — 342,638,214 shares and 2012 — 285,209,848 shares	85,890	71,499
Capital surplus	1,424,198	1,218,283
Accumulated deficit	(141,627)	(123,288)
Accumulated other comprehensive loss	(28,694)	(23,918)
Less treasury stock, at cost; 2013 — 921,721 shares and 2012 — 788,288 shares	(5,080)	(4,664)
Total shareholders’ equity	1,334,726	1,137,951
Total liabilities and shareholders’ equity	$ 2,272,455	$ 1,378,290