Supplemental Cash Flow Information (Tables)

6 Months Ended

Jun. 30, 2012

Supplemental Cash Flow Elements [Abstract]

Net Changes In Components Of Operating Assets And Liabilities

	Six Months Ended June 30,
	2012			2011
(Increase) decrease in:
Accounts receivable	$	6,698		$	(54,810	)
Inventories	28,146			(33,847		)
Other current assets	5,197			(1,727		)
Increase (decrease) in:
Accounts payable	(9,549		)	37,167
Accrued liabilities	(10,568		)	4,182
Net changes in components of operating assets and liabilities	$	19,924		$	(49,035	)