Stock-Based Compensation (Schedule Of Non-Vested Restricted Stock Award and RSU Activity and Changes) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 0
Weighted Average Grant Date Fair Value
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	0	$ 0	$ 4
Restricted Stock [Member] \| Axiall Corporation [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 1
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	3 months
Number of Shares
Number of Shares, Non-vested, beginning balance	100,992
Number of Shares, Vested	(48,845)
Number of Shares, Forfeited	(2,619)
Number of Shares, Non-vested, ending balance	49,528	100,992
Weighted Average Grant Date Fair Value
Weighted Average Fair Value, Non-vested, beginning balance (in dollars per share)	$ 106.53
Weighted Average Fair Value, Vested (in dollars per share)	116.99
Weighted Average Fair Value, Forfeited (in dollars per share)	99.50
Weighted Average Fair Value, Non-vested, ending balance (in dollars per share)	$ 66.46	$ 106.53
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 6	$ 11	3
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized	$ 17
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition	1 year 6 months
Number of Shares
Number of Shares, Non-vested, beginning balance	663,866
Number of Shares, Granted	146,811
Number of Shares, Vested	(95,449)
Number of Shares, Forfeited	(12,439)
Number of Shares, Non-vested, ending balance	702,789	663,866
Weighted Average Grant Date Fair Value
Weighted Average Fair Value, Non-vested, beginning balance (in dollars per share)	$ 56.86
Weighted Average Fair Value, Granted (in dollars per share)	106.58
Weighted Average Fair Value, Vested (in dollars per share)	65.32
Weighted Average Fair Value, Forfeited (in dollars per share)	74.46
Weighted Average Fair Value, Non-vested, ending balance (in dollars per share)	$ 65.79	$ 56.86
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 10	$ 6	$ 4

Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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