Fungible shares issuance ratio.

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Number of equal vesting installments.

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No definition available.

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- Definition

Share based compensation arrangement by share based payment award performance period.

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No definition available.

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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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- Definition

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

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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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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- Definition

General descriptive information regarding an arrangement under which employees and directors receive: (a) awards of equity shares, equity share options, or other equity instruments; or (b) the entity incurs liabilities to them: (1) in amounts based, at least in part, on the price of the entity's shares or other equity instruments; or (2) that require or may require settlement by issuance of the entity's shares. Such an arrangement is usually provided to employees and directors to compensate them, provide performance incentives to them, and to attract or retain their services. May also include pertinent information particular to a plan that is not elsewhere specified in the taxonomy.

+ References

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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).

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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

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

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Stock-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Millions			3 Months Ended		9 Months Ended
	May 11, 2018 $ / shares shares	Feb. 28, 2018 Installment $ / shares shares	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares under stock based compensation			69,400,000		69,400,000
Remaining shares available for future grants under the Plan			10,253,618		10,253,618
Stock option granted		1,610,599
Stock options granted fair value \| $ / shares		$ 10.01
Stock options exercise price \| $ / shares		$ 35.09
Stock-based compensation expense \| $			$ 30	$ 33	$ 88	$ 85
Income tax benefit recognized \| $			$ 6	9	$ 12	18
2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorized shares under stock based compensation	17,800,000
Remaining shares available for future grants under the Plan			17,709,906		17,709,906
Stock-based compensation expense \| $			$ 30	33	$ 88	85
Income tax benefit recognized \| $			$ 6	$ 9	$ 12	$ 18
Stock Options and Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fungible shares issuance ratio					1
Stock Options and Stock Appreciation Rights (SARs) [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fungible shares issuance ratio	1
Other Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fungible shares issuance ratio					3
Other Awards [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fungible shares issuance ratio	2.5
Restricted Stock and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		2,391,933
Restricted stock granted fair value \| $ / shares		$ 35.09
Number of equal annual vesting installments \| Installment		3
Period of option vested over grant date					The restricted stock and restricted stock units vest in three equal annual installments commencing on the first anniversary of the grant date.
Performance-base restricted stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of performance goal					The performance share awards can be earned based on performance against established goals over a three-year performance period.
Performance period					3 years
Performance-base restricted stock [Member] \| Minimum [Member] \| Senior Management Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
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]
Shares granted		449,532
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		14,228
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
TSR Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Description of performance goal					The performance share awards are based entirely on a TSR (total shareholder return) goal. Performance against the TSR goal is determined by comparing the performance of the Company’s TSR with the TSR performance of the members of the OSX (Oil Service Sector) index for the three-year performance period.
Restricted Stock Awards [Member] \| 2018 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	35,432
Restricted stock granted fair value \| $ / shares	$ 40.65