Supplemental Cash Flow Information

12 Months Ended

Dec. 31, 2012

Supplemental Cash Flow Elements [Abstract]

Supplemental Cash Flow Information

14. Supplemental Cash Flow Information

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

	Year Ended December 31,
	2012			2011			2010
(Increase) decrease in:
Accounts receivable	$	(34,299	)	$	(66,208	)	$	(41,648	)
Inventories	14,074			(46,151		)	(16,870		)
Other current assets	(9,593		)	(3,598		)	(4,036		)
Increase (decrease) in:
Accounts payable	53,146			33,049			47,401
Accrued liabilities	(10,263		)	15,977			9,666
Net changes in components of operating assets and liabilities	$	13,065		$	(66,931	)	$	(5,487	)

Payments of interest and commitment fees, net of amounts capitalized, were $41.5 million, $32.9 million and $25.1 million during the years ended December 31, 2012, 2011 and 2010, respectively. We capitalized interest of $3.9 million during 2012 and $0.1 million for both 2011 and 2010.

During the years ended December 31, 2012 and 2011, we received tax refunds, net of amounts paid, of $0.3 million and $0.1 million, respectively. Cash paid for income taxes, net of amounts refunded, was $2.4 million during 2010.

At December 31, 2012, 2011 and 2010, we had incurred liabilities for fixed and intangible asset additions totaling $14.1 million, $2 million and $2.6 million, respectively, which had not been paid at the end of the year. Therefore, these amounts were not included in the caption “Payments to acquire fixed and intangible assets” on the Consolidated Statements of Cash Flows.