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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 |  |  |  |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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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 Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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