Earlier authorized shares under stock based compensation.

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Number of equal vesting installments.

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Remaining shares available for future grants under the Plan.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 10
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Face amount or stated value per share of common stock.

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-Name Accounting Standards Codification
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-SubTopic 10
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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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Unrecognized cost of unvested share-based compensation awards.

+ References

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

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Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

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Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-02(28))
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The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws.

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Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt.

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Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

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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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.

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-Name Accounting Standards Codification
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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).

+ 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

Amount of cash paid related to share-based compensation liabilities.

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- Definition

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

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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.

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No definition available.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Common Stock - Additional Information (Detail)				12 Months Ended
Common Stock - Additional Information (Detail)	Nov. 15, 2016 $ / shares shares	May 18, 2016 $ / shares shares	Feb. 24, 2016 $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2015 USD ($) $ / shares shares	Dec. 31, 2014 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common stock, authorized				1,000,000,000	1,000,000,000
Number of preferred stock, authorized				10,000,000
Common stock, par value \| $ / shares				$ 0.01	$ 0.01
Preferred stock, par value \| $ / shares				$ 0.01
Preferred stock, shares issued				0
Preferred stock, shares outstanding				0
Aggregated cash dividends paid \| $				$ 230,000,000	$ 710,000,000	$ 703,000,000
Stock-based compensation expense \| $				107,000,000	109,000,000	101,000,000
Income tax provision recognized \| $				$ 30,000,000	$ 32,000,000	$ 29,000,000
Earlier authorized shares under stock based compensation				69,400,000
Remaining shares available for future grants under the Plan				27,800,000
Duration of performance-based restricted stock awards, vested				Option plan generally vest over a three-year period starting one year from the date of grant and expire ten years from the date of grant.
Stock option, Minimum Range \| $ / shares				$ 23.94
Stock option, Maximum Range \| $ / shares				77.99
Stock option granted fair value \| $ / shares				$ 6.44	$ 15.41	$ 25.60
Total intrinsic value of options exercised \| $				$ 4,000,000	$ 9,000,000
Total unrecognized compensation cost related to nonvested stock options \| $				$ 45,000,000
Compensation cost not yet recognized, period for recognition				2 years
Total fair value of stock options vested \| $				$ 61,000,000	72,000,000	$ 67,000,000
Cash received from option exercises \| $				4,000,000	7,000,000	108,000,000
Tax benefit realized for the tax deductions from option exercises \| $				$ 0	$ 3,000,000	$ 16,000,000
Shares granted				3,384,325	954,075	708,821
Restricted stock granted fair value \| $ / shares				$ 31.59	$ 53.27	$ 70.14
Total number of restricted stock awards and restricted stock units vested				565,202	405,327	348,981
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock option granted fair value \| $ / shares			$ 6.44
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of performance-based restricted stock awards, vested				The SARs are cash-settled awards and vest over a three-year period from the grant date.
Total unrecognized compensation cost related to nonvested stock options \| $				$ 49,000,000
Compensation cost not yet recognized, period for recognition				2 years
Shares granted			4,618,400	4,618,400
Restricted stock granted fair value \| $ / shares				$ 28.32
Cash paid to settle SARs \| $				$ 20,000,000
Restricted Stock and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of performance-based restricted stock awards, vested				The restricted stock and restricted stock units vest on the third anniversary of the date of grant or in three equal annual installments commencing on the first anniversary of the date of grant.
Shares granted			1,732,095
Restricted stock granted fair value \| $ / shares			$ 28.24
Number of equal annual vesting installments				3
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.
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 index for the three-year performance period.
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested stock options \| $				$ 101,000,000
Compensation cost not yet recognized, period for recognition				2 years
Shares granted	1,435,450	44,520
Restricted stock granted fair value \| $ / shares	$ 36.04	$ 31.45		$ 31.59	$ 53.27	$ 70.14
Total number of restricted stock awards and restricted stock units vested				565,202	405,327	348,981
Minimum [Member] \| Performance-base restricted stock [Member] \| Senior Management Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			0
Maximum [Member] \| Performance-base restricted stock [Member] \| Senior Management Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			341,780