Consolidated Balance Sheets (Unaudited) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 1,393	$ 1,313
Accounts receivable, net	1,327	1,214
Inventories	955	918
Prepaid expenses and other current assets	59	32
Total current assets	3,734	3,477
Property, plant and equipment, net	6,921	6,920
Operating lease right-of-use assets	467	461
Goodwill	1,082	1,083
Customer relationships, net	419	444
Other intangible assets, net	160	168
Equity method investments	1,029	1,059
Other assets, net	238	223
Total assets	14,050	13,835
Current liabilities
Accounts payable	603	536
Accrued and other liabilities	723	821
Total current liabilities	1,326	1,357
Long-term debt, net	3,547	3,566
Deferred income taxes	1,385	1,368
Pension and other post-retirement benefits	378	391
Operating lease liabilities	383	376
Other liabilities	206	199
Total liabilities	7,225	7,257
Commitments and contingencies (Note 13)
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 134,651,380 shares issued at March 31, 2021 and December 31, 2020, respectively	1	1
Common stock, held in treasury, at cost; 6,520,062 and 6,821,174 shares at March 31, 2021 and December 31, 2020, respectively	(379)	(401)
Additional paid-in capital	564	569
Retained earnings	6,145	5,938
Accumulated other comprehensive loss	(70)	(64)
Total Westlake Chemical Corporation stockholders' equity	6,261	6,043
Noncontrolling interests	564	535
Total equity	6,825	6,578
Total liabilities and equity	$ 14,050	$ 13,835
Preferred stock, par value, in dollars per share	$ 0.01	$ 0.01
Common stock, par value, in dollars per share	$ 0.01	$ 0.01
Preferred stock, shares outstanding	0	0
Preferred stock, shares authorized	50,000,000	50,000,000
Common stock, shares authorized	300,000,000	300,000,000
Common Stock [Member]
Stockholders' equity
Total equity	$ 1	$ 1
Common Stock, Shares, Issued	134,651,380	134,651,380
Common Stock, Held in Treasury [Member]
Stockholders' equity
Total equity	$ (379)	$ (401)
Treasury Stock, Shares	6,520,062	6,821,174

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).