Stock-based Compensation and Outstanding Awards - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 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
Restricted Stock and Restricted Stock Units [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock based awards, shares granted	191,995
Weighted average grant date fair value, Granted	$ 15.30
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

Performance based restricted stock awards granted in percent.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, 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 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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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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Gross number of share options (or share units) granted during the period.

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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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