Earnings Per Share (Tables)

9 Months Ended

Sep. 30, 2011

Earnings Per Share [Abstract]

Reconciliation of Earnings Per Share

							(Stated in millions, except per share amounts)
	2011						2010
	Schlumberger				Earnings per		Schlumberger				Earnings per
	Income from		Average		Share from		Income from				Share from
	Continuing		Shares		Continuing		Continuing		Average Shares		Continuing
	Operations		Outstanding		Operations		Operations		Outstanding		Operations
Third Quarter
Basic	$	1,301		1,345	$	0.97	$	1,734		1,249	$	1.39
Assumed exercise of stock options		—		9				—		7
Unvested restricted stock		—		3				—		2
Diluted	$	1,301		1,357	$	0.96	$	1,734		1,258	$	1.38

	Schlumberger				Earnings per		Schlumberger				Earnings per
	Income from		Average		Share from		Income from				Share from
	Continuing		Shares		Continuing		Continuing		Average Shares		Continuing
	Operations		Outstanding		Operations		Operations		Outstanding		Operations
Nine Months
Basic	$	3,364		1,352	$	2.49	$	3,224		1,212	$	2.66
Assumed conversion of debentures		—		—				3		5
Assumed exercise of stock options		—		10				—		8
Unvested restricted stock		—		3				—		2
Diluted	$	3,364		1,365	$	2.46	$	3,227		1,227	$	2.63

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share

	(Stated in millions)
	2011		2010
Third Quarter		14		14
Nine Months		6		13