CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 2,100	$ 1,415	$ 3,367	$ 2,720
Currency translation adjustments
Unrealized net change arising during the period	(157)	(203)	(234)	(93)
Marketable securities
Unrealized gain arising during the period	11		83
Derivatives
Net derivatives gain (loss) on hedge transactions	49	(332)	(104)	(177)
Reclassification to net income of net realized (gain) loss (see Note 11)	(34)	260	45	150
Actuarial loss
Actuarial (loss) gain arising during the period	(6)	6	(6)	(21)
Amortization to net income of net actuarial loss (see Note 15)	76	43	152	86
Prior service cost
Amortization to net income of net prior service cost (see Note 15)	31	31	63	62
Income taxes on pension and other postretirement benefit plans	(15)	(13)	(31)	(23)
Comprehensive income	2,055	1,207	3,335	2,704
Comprehensive income attributable to noncontrolling interests	5	12	13	17
Comprehensive income attributable to Schlumberger	$ 2,050	$ 1,195	$ 3,322	$ 2,687