Earnings per Share (Tables)

9 Months Ended

Sep. 30, 2017

Earnings Per Share [Abstract]

Schedule Of Net Income Attributable To Common Stockholders

Diluted earnings per share include the effect of certain stock options.

	Three Months Ended September 30,						Nine Months Ended September 30,
	2017			2016			2017			2016
Net income attributable to Westlake Chemical    Corporation	$	210,832		$	65,662		$	501,849		$	299,914
Less:
Net income attributable to participating securities	(1,117		)	(294		)	(2,630		)	(1,347		)
Net income attributable to common shareholders	$	209,715		$	65,368		$	499,219		$	298,567

Reconciliation Of Denominator For Basic And Diluted Earnings Per Share

The following table reconciles the denominator for the basic and diluted earnings per share computations shown in the consolidated statements of operations:

	Three Months Ended September 30,				Nine Months Ended September 30,
	2017		2016		2017		2016
Weighted average common shares—basic	129,069,186		128,793,661		129,033,597		129,519,577
Plus incremental shares from:
Assumed exercise of options	819,782		586,295		756,368		584,320
Weighted average common shares—diluted	129,888,968		129,379,956		129,789,965		130,103,897
Earnings per common share attributable to    Westlake Chemical Corporation:
Basic	$	1.62	$	0.51	$	3.87	$	2.31
Diluted	$	1.61	$	0.51	$	3.85	$	2.29