Earlier authorized shares under stock based compensation.

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Performance based restricted stock awards granted in percent.

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Remaining shares available for future grants under the Plan.

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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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Face amount or stated value per share of common stock.

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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.

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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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The cash outflow to reacquire common stock during the 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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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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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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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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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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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 equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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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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Amount of stock repurchase plan authorized.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Common Stock - Additional Information (Detail) - USD ($)				12 Months Ended
	Aug. 28, 2015	May. 13, 2015	Feb. 25, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Sep. 30, 2015
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				$ 0.01	$ 0.01
Preferred stock, par value				$ 0.01
Preferred stock, shares issued				0
Preferred stock, shares outstanding				0
Aggregated cash dividends paid				$ 710,000,000	$ 703,000,000	$ 389,000,000
Share repurchase program, authorized amount							$ 3,000,000,000
Common stock repurchased (Treasury stock)				44,000,000	11,600,000
Common stock repurchased, average price per share				$ 50.53	$ 66.97
Common stock repurchased, aggregate amount				$ 2,221,000,000	$ 779,000,000
Compensation cost charged against income for share-based compensation arrangements				109,000,000	101,000,000	92,000,000
Income tax benefit recognized for share-based compensation arrangements				$ 28,000,000	$ 35,000,000	$ 28,000,000
Earlier authorized shares under stock based compensation				39,500,000
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.
Remaining shares available for future grants under the Plan				6,200,000
Stock option, Minimum Range				$ 12.15
Stock option, Maximum Range				77.99
Weighted-average fair value of options granted				$ 15.41	$ 25.60	$ 24.11
Total intrinsic value of options exercised				$ 9,000,000	$ 111,000,000
Total unrecognized compensation cost related to nonvested stock options				$ 95,000,000
Weighted-average period recognition of unrecognized compensation cost related to nonvested RSA's				2 years
Total fair value of stock options vested				$ 72,000,000	67,000,000	$ 64,000,000
Cash received from option exercises				7,000,000	108,000,000	58,000,000
Tax benefit realized for the tax deductions from option exercises				$ 7,000,000	$ 44,000,000	$ 39,000,000
Restricted stock granted				954,075	708,821	822,281
Restricted stock granted fair value				$ 53.27	$ 70.14	$ 63.69
Description of performance goal				Performance against the ROC goal is determined by comparing the performance of the Company's actual ROC performance average for each of the three years of the performance period against the ROC goal set by the Company's Compensation Committee.
Total number of restricted stock awards and restricted stock units granted				405,327	348,981	368,984
Restricted Stock and Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted			653,750
Restricted stock granted fair value			$ 54.74
TSR Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based restricted stock awards granted in percent			50.00%
ROC Award [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance based restricted stock awards granted in percent			50.00%
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Duration of performance-based restricted stock awards, vested				The stock options vest over a three-year period from the grant date while the restricted stock and restricted stock units vest on the third anniversary of the date of grant.
Total unrecognized compensation cost related to nonvested stock options				$ 57,000,000
Weighted-average period recognition of unrecognized compensation cost related to nonvested RSA's				2 years
Restricted stock granted	75,000	26,992
Restricted stock granted fair value	$ 41.65	$ 51.88		$ 53.27	$ 70.14	$ 63.69
Performance based restricted stock awards vested, number of years	3 years		3 years
Total number of restricted stock awards and restricted stock units granted				405,327	348,981	368,984
Minimum [Member] \| Performance-base restricted stock [Member] \| Senior Management Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted			0
Maximum [Member] \| Performance-base restricted stock [Member] \| Senior Management Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock granted			396,666