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Common Stock - Additional Information (Detail) $ / shares in Units, $ in Millions				12 Months Ended
	May 11, 2018 $ / shares shares	Feb. 28, 2018 $ / shares shares	Dec. 20, 2017 USD ($) $ / shares shares	Dec. 31, 2018 USD ($) Installment $ / shares shares	Dec. 31, 2017 USD ($) $ / shares shares	Dec. 31, 2016 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 \| $				$ 76	$ 76	$ 230
Stock-based compensation expense \| $				110	124	107
Income tax provision recognized \| $				$ 16	$ 24	$ 30
Earlier authorized shares under stock based compensation \| shares				69,400,000
Duration of performance-based restricted stock awards, vested				Options granted under our stock 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				$ 10.01	$ 9.68	$ 6.44
Total intrinsic value of options exercised \| $				$ 54	$ 13
Total unrecognized compensation cost related to nonvested stock options \| $				$ 25
Compensation cost not yet recognized, period for recognition				3 years
Total fair value of stock options vested \| $				$ 26	70	$ 61
Cash received from option exercises \| $				54	13	4
Tax benefit (expense) realized for the tax deductions from option exercises \| $				$ 2	$ (2)	$ 0
Stock options granted				1,610,599	6,961,041	3,672,411
Weighted average exercise price per share of options \| $ / shares				$ 35.09	$ 36.51	$ 28.26
Stock Appreciation Rights (SARs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock appreciation rights exchange percentage			94.75%
Cash payment of stock appreciation rights \| $			$ 14
Cash paid to settle SARs \| $				$ 0
Compensation cost recognized \| $				$ 0	$ 8	$ 20
Shares granted				14,228	14,400
Restricted stock granted fair value \| $ / shares				$ 35.09	$ 38.86
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			3,613,707
Weighted average exercise price per share of options \| $ / shares			$ 34.32
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 in three equal annual installments commencing on the first anniversary of the date of grant.
Shares granted		2,391,933		2,657,115	1,738,589	3,384,325
Restricted stock granted fair value \| $ / shares		$ 35.09		$ 35.17	$ 38.74	$ 31.59
Number of equal annual vesting installments \| Installment				3
Total number of restricted stock awards and restricted stock units vested				1,242,682	1,018,206	565,202
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-base restricted stock [Member] \| Senior Management Employees [Member] \| Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		0
Performance-base restricted stock [Member] \| Senior Management Employees [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		449,532
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]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost related to nonvested stock options \| $				$ 108
Compensation cost not yet recognized, period for recognition				2 years
Restricted stock granted fair value \| $ / shares				$ 35.17	$ 38.74	$ 31.59
Total number of restricted stock awards and restricted stock units vested				1,242,682	1,018,206	565,202
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				17,700,000
2018 Plan [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	35,432
Restricted stock granted fair value \| $ / shares	$ 40.65