Earnings Per Share - Reconciliation of Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Schlumberger Net Income
Basic	$ 644	$ 545	$ 1,599	$ 749
Diluted	$ 644	$ 545	$ 1,599	$ 749
Average Shares Outstanding
Basic	1,385	1,385	1,385	1,388
Assumed exercise of stock options		1	1	2
Unvested restricted stock	7	6	7	5
Diluted	1,392	1,392	1,393	1,395
Earnings per Share
Basic	$ 0.46	$ 0.39	$ 1.15	$ 0.54
Diluted	$ 0.46	$ 0.39	$ 1.15	$ 0.54

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of call options and warrants using the treasury stock method.

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