Supplemental Cash Flow Information

12 Months Ended

Dec. 31, 2013

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,
	2013			2012			2011
(Increase) decrease in:
Accounts receivable	$	(96,300	)	$	(34,299	)	$	(66,208	)
Inventories	1,720			14,074			(46,151		)
Other current assets	(39,170		)	(9,593		)	(3,598		)
Increase (decrease) in:
Accounts payable	41,718			53,146			33,049
Accrued liabilities	45,846			(10,263		)	15,977
Net changes in components of operating assets and liabilities	$	(46,186	)	$	13,065		$	(66,931	)

Payments of interest and commitment fees, net of amounts capitalized, were $49.7 million, $41.5 million and $32.9 million during the years ended December 31, 2013, 2012 and 2011, respectively. We capitalized interest of $13.3 million, $3.9 million and $0.1 million during the years ended December 31, 2013, 2012 and 2011.

During the year ended December 31, 2013, we paid taxes of $0.6 million. 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.

At December 31, 2013, 2012 and 2011, we had incurred liabilities for fixed and intangible asset additions totaling $52.5 million, $14.1 million and $2 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” under Cash Flows from Investing Activities in the Consolidated Statements of Cash Flows.

At December 31, 2013, we had incurred liabilities for other asset additions totaling $0.1 million that had not been paid at the end of the year, and, therefore, were not included in the caption "Other, net" under Cash Flows from Investing Activities in the Consolidated Statements of Cash Flows.