Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2017

Summary Of Assets And Liabilities Accounted At Fair Value On A Recurring Basis

The following tables summarize, by level within the fair value hierarchy, the Company's assets and liabilities that were accounted for at fair value on a recurring basis:



	March 31, 2017
	Level 1			Level 2			Total
Derivative instruments
Risk management assets—Commodity forward contracts	$	406		$	6,471		$	6,877
Risk management liabilities—Commodity forward contracts	(6,710		)	(960		)	(7,670		)

	December 31, 2016
	Level 1			Level 2			Total
Derivative instruments
Risk management assets—Commodity forward contracts	$	878		$	14,108		$	14,986
Risk management liabilities—Commodity forward contracts	(6,854		)	(367		)	(7,221		)

Summary Of Carrying And Fair Values Of Long-Term Debt

The carrying and fair values of the Company's long-term debt are summarized in the table below. The fair value of the Company's long-term debt instruments is determined using a market approach, based upon quotes from financial reporting services. Because the Company's long-term debt instruments may not be actively traded, the inputs used to measure the fair value of the Company's long-term debt are classified as Level 2 inputs within the fair value hierarchy.



	March 31, 2017				December 31, 2016
	Carrying Value		Fair Value		Carrying Value		Fair Value
Revolving credit facility	$	250,000	$	250,000	$	325,000	$	325,000
4.625% Westlake 2021 Senior Notes	624,793		649,354		651,630		650,847
4.625% Subsidiary 2021 Senior Notes	63,207		65,639		66,069		65,775
3.60% senior notes due 2022	250,000		254,443		248,109		251,725
4.875% Westlake 2023 Senior Notes	433,793		451,761		447,224		451,301
4.875% Subsidiary 2023 Senior Notes	16,207		16,873		16,747		16,501
3.60% 2026 Senior Notes	750,000		735,870		739,243		722,055
Loan related to tax-exempt waste disposal revenue bonds due 2027	10,889		10,889		10,889		10,889
6 ½% senior notes due 2029	100,000		110,000		99,084		112,433
6 ¾% senior notes due 2032	250,000		258,760		248,117		258,818
6 ½% 2035 GO Zone Senior Notes	89,000		101,760		88,161		100,323
6 ½% 2035 IKE Zone Senior Notes	65,000		74,298		64,398		73,270
5.0% 2046 Senior Notes	700,000		717,864		673,983		691,712