Performance based restricted stock awards granted in percent.

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- Definition

Performance based restricted stock awards performance goal period.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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- Definition

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).

+ References

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- Definition

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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- Definition

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.

+ References

No definition available.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Stock-based Compensation and Outstanding Awards - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option granted			521,157
Weighted-average grant-date fair value of options granted			$ 6.02
Stock-based compensation expense	$ 4	$ 4	$ 12	$ 12
Restricted Stock and Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based awards, shares granted			256,382
Weighted average grant date fair value, Granted			$ 14.99
Performance-base restricted stock [Member] \| Minimum [Member] \| Senior Management Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based awards, shares granted			0
Performance-base restricted stock [Member] \| Maximum [Member] \| Senior Management Employees [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based awards, shares granted			331,372
Stock Options [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based awards, vested, number of years			3 years
TSR metric [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance based restricted stock awards granted in percent			50.00%
Performance based restricted stock awards goals over performance period			3 years
EBITDA metric [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance based restricted stock awards granted in percent			25.00%
Performance based restricted stock awards goals over performance period			3 years
Return on Capital Employed (ROCE) metric [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance based restricted stock awards granted in percent			25.00%
Performance based restricted stock awards goals over performance period			3 years