Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 380,519	$ 662,525
Marketable securities	0	520,144
Accounts receivable, net	1,070,501	508,532
Inventories	744,536	434,060
Prepaid expenses and other current assets	54,868	14,489
Restricted cash	169,320	0
Deferred income taxes	0	35,439
Total current assets	2,419,744	2,175,189
Property, plant and equipment, net	6,450,947	3,004,067
Other assets, net
Goodwill	925,700	62,016
Deferred charges and other assets, net	310,456	176,625
Total other assets, net	2,026,358	390,029
Total assets	10,897,049	5,569,285
Current liabilities
Accounts and notes payable	503,388	235,329
Accrued liabilities	552,581	287,313
Term loan	148,681	0
Total current liabilities	1,204,650	522,642
Long-term debt, net	3,680,585	758,148
Deferred income taxes	1,607,084	575,603
Pension and other post-retirement benefits	434,067	122,821
Other liabilities	146,526	28,140
Total liabilities	7,072,912	2,007,354
Commitments and contingencies (Notes 10 and 20)
Stockholders' equity
Preferred stock, $0.01 par value, 50,000,000 shares authorized; no shares issued and outstanding	0	0
Common stock, $0.01 par value, 300,000,000 shares authorized; 134,651,380 and 134,663,244 shares issued at September 30, 2016 and December 31, 2015, respectively	1,347	1,347
Common stock, held in treasury, at cost; 5,752,377 and 4,444,898 shares at September 30, 2016 and December 31, 2015, respectively	(319,980)	(258,312)
Additional paid-in capital	546,519	542,148
Retained earnings	3,337,968	3,109,987
Accumulated other comprehensive loss	(108,126)	(129,292)
Total Westlake Chemical Corporation stockholders' equity	3,457,728	3,265,878
Noncontrolling interests	366,409	296,053
Total equity	3,824,137	3,561,931
Total liabilities and equity	10,897,049	5,569,285
Customer Relationships [Member]
Other assets, net
Finite-lived intangible assets, net	604,551	52,677
Other Intangible Assets, Net [Member]
Other assets, net
Finite-lived intangible assets, net	$ 185,651	$ 98,711