Supplemental Cash Flow Information

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



	Year Ended December 31,
	2017			2016			2015
(Increase) decrease in:
Accounts receivable	$	(140,948	)	$	(9,859	)	$	99,384
Inventories	49,055			(54,361		)	3,811
Deferred charges	(3,622		)	(3,902		)	(11,916		)
Other current assets	(410		)	3,059			6,417
Increase (decrease) in:
Accounts payable	97,569			(17,426		)	(101,581		)
Accrued liabilities	8,512			(8,161		)	9,257
Net changes in components of operating assets and liabilities	$	10,156		$	(90,650	)	$	5,372

Payments of interest and commitment fees were $168.3 million, $157.4 million and $86.8 million during the years ended December 31, 2017, 2016 and 2015, respectively. We capitalized interest of $15.0 million, $26.6 million and $17.1 million during the years ended December 31, 2017, 2016 and 2015.

During the years ended December 31, 2017, 2016 and 2015, we paid taxes of $1.0 million, $1.3 million and $0.9 million.

At December 31, 2017, 2016 and 2015, we had incurred liabilities for fixed and intangible asset additions totaling $39.7 million, $33.7 million and $68.6 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” under Cash Flows from Investing Activities in the Consolidated Statements of Cash Flows.

During the year ended December 31, 2015, as a result of our Enterprise acquisition, we acquired the 50% ownership interest in each of CHOPS and SEKCO as previously held by Enterprise, resulting in 100% ownership interest by us in each of these subsidiaries. As a result, we recorded a one-time $332.4 million non-cash gain from the step up in basis in our historical 50% ownership interest in each of CHOPS and SEKCO to fair value (resulting from the fair value assigned to the 50% ownership interest in each of CHOPS and SEKCO that we acquired from Enterprise, as derived from the preliminary purchase price allocation). This also results in the consolidation of CHOPS and SEKCO by us, resulting in the inclusion of the operating assets and liabilities on our Consolidated Balance Sheet. As 50% of the operating assets and liabilities of CHOPS and SEKCO were based on our historical interest with no cash impact, these amounts relating to our historical interest were not included in net changes in components of operating assets and liabilities in the Consolidated Statements of Cash Flows in 2015.