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, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Schlumberger Income from Continuing Operations
Basic	$ 989	$ 1,949	$ 3,088	$ 5,341
Diluted	$ 989	$ 1,949	$ 3,088	$ 5,341
Average shares outstanding:
Basic	1,265	1,294	1,270	1,300
Assumed exercise of stock options	3	12	4	10
Unvested restricted stock	4	4	4	4
Diluted	1,272	1,310	1,278	1,314
Earnings per Share from Continuing Operations
Basic	$ 0.78	$ 1.51	$ 2.43	$ 4.11
Diluted	$ 0.78	$ 1.49	$ 2.42	$ 4.07