Note 11. Derivative Instruments (Tables)

9 Months Ended

Sep. 30, 2011

Schedule of Derivative Liabilities at Fair Value [Table Text Block]

	September 30, 2011		December 31, 2010
Other current assets	$	14,341	$	—
Other non-current assets and deferred charges		21,376		—
Current derivative contract liabilities		—		20,016
Other non-current liabilities		—		779
Total fair value assets	$	35,717	$	—
Total fair value liabilities	$	—	$	20,795

Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Table Text Block]

	Three Months Ended September 30,					Nine Months Ended September 30,
	2011		2010			2011		2010
Sales of products	$	5,994	$	(5,348	)	$	6,697	$	1,003
Gain (loss) on derivatives contracts		40,382		(13,195	)		38,907		(11,196	)

Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block]

	Metric tonnes under contract				Average price per pound
	Zinc		Lead		Zinc		Lead
Contracts on provisional sales
2011 settlements		5,125		2,800	$	1.03	$	1.00
Contracts on forecasted sales
2011 settlements		2,300		2,275	$	0.99	$	1.05
2012 settlements		26,650		18,000	$	1.11	$	1.11
2013 settlements		8,275		11,150	$	1.14	$	1.17