Note 5. Income Taxes (Tables)

12 Months Ended

Dec. 31, 2011

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

	2011		2010			2009
Current:
Federal	$	3,823	$	10,063		$	(1,277	)
State		752		6,694			33
Foreign		459		459			664
Total current income tax provision		5,034		17,216			(580	)
Federal and state deferred income tax (benefit) provision		76,944		(140,748	)		(7,100	)
Total income tax (benefit) provision	$	81,978	$	(123,532	)	$	(7,680	)

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

	2011			2010			2009
Domestic	$	244,833		$	(66,348	)	$	59,779
Foreign		(11,691	)		(8,201	)		367
Total	$	233,142		$	(74,549	)	$	60,146

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	2011					2010					2009
Computed “statutory” (benefit) provision	$	81,600		35	%	$	(26,092	)	(35	)%	$	21,051		35	%
Percentage depletion		(13,751	)	(6	)		(8,858	)	(12	)		(7,953	)	(16	)
Net increase (utilization) of U.S. and foreign tax loss carryforwards		3,822		2			2,713		3			(13,098	)	(19	)
Change in valuation allowance other than utilization		—		—			(88,069	)	(118	)		(7,100	)	(12	)
Tax loss carryback from change in tax law		—		—			—		—			(1,989	)	(3	)
State taxes, net of federal taxes		10,890		5			(4,717	)	(6	)		33		—
Effect of U.S. AMT,  foreign taxes other		(583	)	(1	)		1,491		2			1,376		2
	$	81,978		35	%	$	(123,532	)	(166	)%	$	(7,680	)	(13	)%

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	December 31,
	2011			2010
Deferred tax assets:
Accrued reclamation costs	$	62,225		$	129,687
Deferred exploration		18,585			14,596
Foreign net operating losses		20,234			16,850
Federal net operating losses		47,875			36,744
State net operating losses		2,445			924
AMT credit carryforwards		15,210			10,879
Unrealized loss on derivatives contracts		—			8,459
Pension and benefit obligation		9,940			3,198
Miscellaneous		16,002			14,132
Total deferred tax assets		192,516			235,469
Valuation allowance		(22,895	)		(19,073	)
Total deferred tax assets		169,621			216,396
Deferred tax liabilities:
Unrealized gain on derivatives contracts		(13,293	)		—
Properties, plants and equipment		(40,490	)		(29,037	)
Total deferred tax liabilities		(53,783	)		(29,037	)
Net deferred tax asset	$	115,838		$	187,359

Summary of Positions for which Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table Text Block]

	2011			2010			2009
Balance at beginning of year	$	(19,073	)	$	(104,429	)	$	(138,848	)
Increase related to non-utilization of net operating loss carryforwards and non-recognition of deferred tax assets due to uncertainty of recovery		(3,822	)		(2,713	)		—
Decrease related to net recognition of deferred tax assets		—			88,069			7,100
Decrease related to utilization and expiration of deferred tax assets		—			—			27,319
Balance at end of year	$	(22,895	)	$	(19,073	)	$	(104,429	)