Supplemental Cash Flow Information (Tables)

3 Months Ended

Mar. 31, 2012

Supplemental Cash Flow Information [Abstract]

Net Changes In Components Of Operating Assets And Liabilities

	Three Months Ended March 31,
	2012			2011
(Increase) decrease in:
Accounts receivable	$	(55,904	)	$	(96,899	)
Inventories		(2,307	)		20,211
Other current assets		(2,327	)		(7,890	)
Increase (decrease) in:
Accounts payable		52,055			51,249
Accrued liabilities		(8,785	)		607
Net changes in components of operating assets and liabilities	$	(17,268	)	$	(32,722	)