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Common Stock - Additional Information (Detail) |  |  |  | 3 Months Ended | 12 Months Ended
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Dec. 20, 2017 USD ($) $ / shares shares | May 17, 2017 $ / shares shares | Feb. 22, 2017 $ / shares shares | Jun. 30, 2016 shares | Dec. 31, 2017 USD ($) Installment $ / shares shares | Dec. 31, 2016 USD ($) $ / shares shares | Dec. 31, 2015 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Number of common stock, authorized | shares |  |  |  |  | 1,000,000,000 | 1,000,000,000 |
Number of preferred stock, authorized | shares |  |  |  |  | 10,000,000 |  |
Common stock, par value | $ / shares |  |  |  |  | $ 0.01 | $ 0.01 |
Preferred stock, par value | $ / shares |  |  |  |  | $ 0.01 |  |
Preferred stock, shares issued | shares |  |  |  |  | 0 |  |
Preferred stock, shares outstanding | shares |  |  |  |  | 0 |  |
Aggregated cash dividends paid |  |  |  |  | $ 76,000,000 | $ 230,000,000 | $ 710,000,000
Stock-based compensation expense |  |  |  |  | 124,000,000 | 107,000,000 | 109,000,000
Income tax provision recognized |  |  |  |  | $ 24,000,000 | $ 30,000,000 | $ 32,000,000
Earlier authorized shares under stock based compensation | shares |  |  |  | 69,400,000 |  |  |
Remaining shares available for future grants under the Plan | shares |  |  |  |  | 17,800,000 |  |
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 |  |
Weighted average grant-date fair value of options | $ / shares |  |  |  |  | $ 9.68 | $ 6.44 | $ 15.41
Total intrinsic value of options exercised |  |  |  |  | $ 13,000,000 | $ 4,000,000 |
Total unrecognized compensation cost related to nonvested stock options |  |  |  |  | $ 36,000,000 |  |
Compensation cost not yet recognized, period for recognition |  |  |  |  | 2 years |  |
Total fair value of stock options vested |  |  |  |  | $ 70,000,000 | 61,000,000 | $ 72,000,000
Cash received from option exercises |  |  |  |  | 13,000,000 | 4,000,000 | 7,000,000
Tax benefit (expense) realized for the tax deductions from option exercises |  |  |  |  | $ (2,000,000) | $ 0 | 3,000,000
Cash payment of stock appreciation rights |  |  |  |  |  |  | $ 2,221,000,000
Weighted average exercise price per share of options | $ / shares |  |  |  |  | $ 36.51 | $ 28.26 | $ 54.74
Shares granted | shares |  |  |  |  | 1,738,589 | 3,384,325 | 954,075
Restricted stock granted fair value | $ / shares |  |  |  |  | $ 38.74 | $ 31.59 | $ 53.27
Total number of restricted stock awards and restricted stock units vested | shares |  |  |  |  | 1,018,206 | 565,202 | 405,327
Stock Appreciation Rights (SARs) [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Stock-based compensation expense |  |  |  |  | $ 11,000,000 |  |
Total unrecognized compensation cost related to nonvested stock options |  |  |  |  | $ 16,000,000 |  |
Compensation cost not yet recognized, period for recognition |  |  |  |  | 2 years |  |
Stock appreciation rights exchange percentage | 94.75% |  |  |  |  |  |
Cash payment of stock appreciation rights | $ 14,000,000 |  |  |  |  |  |
Increase additional paid-in capital |  |  |  |  | $ 20,000,000 |  |
Cash paid to settle SARs |  |  |  |  | 2,000,000 |  |
Compensation cost recognized |  |  |  |  | $ 8,000,000 | $ 20,000,000 |
Shares granted | shares |  |  |  |  | 14,400 | 4,618,400 |
Restricted stock granted fair value | $ / shares |  |  |  |  | $ 38.86 | $ 28.32 |
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 | shares |  |  | 1,504,450 |  |  |  |
Restricted stock granted fair value | $ / shares |  |  | $ 38.86 |  |  |  |
Number of equal annual vesting installments | Installment |  |  |  |  | 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 |  |  |  |  | $ 99,000,000 |  |
Compensation cost not yet recognized, period for recognition |  |  |  |  | 2 years |  |
Shares granted | shares |  | 36,701 |  |  |  |  |
Restricted stock granted fair value | $ / shares |  | $ 33.38 |  |  | $ 38.74 | $ 31.59 | $ 53.27
Total number of restricted stock awards and restricted stock units vested | shares |  |  |  |  | 1,018,206 | 565,202 | 405,327
Stock Options [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Weighted average grant-date fair value of options | $ / shares | $ 8.47 |  |  |  |  |  |
Stock options granted | shares | 3,613,707 |  |  |  |  |  |
Weighted average exercise price per share of options | $ / shares | $ 34.32 |  |  |  |  |  |
Minimum [Member] | Performance-base restricted stock [Member] | Senior Management Employees [Member] |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |
Shares granted | shares |  |  | 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 | shares |  |  | 388,380 |  |  |  |

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