Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 14,304	$ 5,940
Adjustments to reconcile net income to net cash provided by operating activities:
Depletion, depreciation and amortization	15,283	14,672
(Gain)/Loss on disposal of property, plant and equipment	36	(5)
Loss on long-term investments	562	0
Deferred taxes	1,830	(3,501)
Foreign currency transaction gain, net	(4,237)	(2,931)
Abandonment of non-producing property	0	2,835
Accretion of asset retirement obligation	167	153
Amortization of debt issuance costs	557	314
Accretion of convertible debenture debt discount	3,832	9
Share based compensation and other benefits	4,246	3,772
Changes in operating assets and liabilities:
Inventories	(34,017)	(1,566)
Trade receivables	(4,350)	(3,182)
Accrued compensation and benefits	(780)	857
Accounts payable	11,567	3,845
Property, production and franchise taxes payable	1,612	441
Income taxes payable	669	(2,847)
Workers compensation	384	0
Other	3,837	(3,658)
NET CASH PROVIDED BY OPERATING ACTIVITIES	15,502	15,148
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures	(29,406)	(22,720)
Proceeds from disposal of property, plant and equipment	19	8
Purchases of investments	(21,996)	(5,250)
Proceeds from maturities of investments	24,025	4,461
NET CASH USED IN INVESTING ACTIVITIES	(27,358)	(23,501)
CASH FLOWS FROM FINANCING ACTIVITIES
Payments on debt and capital lease obligations	(164,787)	0
Payments for issuance costs	0	(219)
Issuance of common stock	56	29
NET CASH USED IN FINANCING ACTIVITIES	(164,731)	(190)
CASH AND CASH EQUIVALENTS
Net decrease	(176,587)	(8,543)
Balance at beginning of period	379,680	109,097
BALANCE AT END OF PERIOD	$ 203,093	$ 100,554