Supplemental Cash Flow Information

3 Months Ended

Mar. 31, 2013

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

10. Supplemental Cash Flow Information

The following table provides information regarding the net changes in components of operating assets and liabilities.

	Three Months Ended March 31,
	2013			2012
(Increase) decrease in:
Accounts receivable	$	(85,915	)	$	(55,904	)
Inventories	7,947			(2,307		)
Other current assets	4,736			(2,327		)
Increase (decrease) in:
Accounts payable	57,048			52,055
Accrued liabilities	6,019			(8,785		)
Net changes in components of operating assets and liabilities	$	(10,165	)	$	(17,268	)

Payments of interest and commitment fees were $2.8 million and $5.2 million for the three months ended March 31, 2013 and March 31, 2012, respectively.

At March 31, 2013 and March 31, 2012, we had incurred liabilities for fixed and intangible asset additions totaling $5 million and $4.1 million, respectively, that had not been paid at the end of the first quarter, and, therefore, were not included in the caption “Payments to acquire fixed and intangible assets” under Cash Flows from Investing Activities in the Unaudited Condensed Consolidated Statements of Cash Flows.

At March 31, 2013, we had incurred liabilities for other asset additions totaling $0.3 million that had not been paid at the end of the first quarter, and, therefore, were not included in the caption "Other, net" under Cash Flows from Investing Activities in the Unaudited Condensed Consolidated Statements of Cash Flows.