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Consideration Paid for Acquired Entities, Net of Cash Acquired, Debt Assumed, and Other Adjustments

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Represents the number of stores.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Acquisitions and Dispositions (Acquistions) (Detail) $ in Millions	1 Months Ended	3 Months Ended								12 Months Ended
	Jan. 31, 2017 distribution_center	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Jan. 31, 2018 employees store	Jul. 31, 2016 USD ($)	Jun. 30, 2016	Dec. 31, 2013
Business Acquisition [Line Items]
Net sales		$ 3,645	$ 3,817	$ 4,131	$ 3,781	$ 3,682	$ 3,776	$ 3,804	$ 3,486	$ 15,374	$ 14,748	$ 14,270
Consideration paid for acquired entities, net of cash acquired, debt assumed, and other adjustments										$ 108	$ 74	43
Number Of Distributors (more than) \| distribution_center	200
Taiwan Chlorine Industries (“TCI”)
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent						40.00%					40.00%				40.00%	60.00%
Business combination, recognized identifiable assets acquired and liabilities assumed, net												$ 100
MetoKote Corporation
Business Acquisition [Line Items]
Business combination, recognized identifiable assets acquired and liabilities assumed, net														$ 306
ProCoatings
Business Acquisition [Line Items]
Number of stores \| store													23
Entity number of employees \| employees													100
China Petrochemical Development Corporation \| Taiwan Chlorine Industries (“TCI”)
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent															40.00%
China Petrochemical Development Corporation \| Axiall Corporation
Business Acquisition [Line Items]
Noncontrolling interest, ownership percentage by parent															40.00%