CONSOLIDATED STATEMENT OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 562	$ (73)	$ 1,317	$ (10,868)
Currency translation adjustments
Unrealized net change arising during the period	30	(94)	6	(200)
Cash flow hedges
Net gain (loss) on cash flow hedges	(9)	36	13	(195)
Reclassification to net income (loss) of net realized (gain) loss	(2)	7	(7)	12
Pension and other postretirement benefit plans
Amortization to net income (loss) of net actuarial loss	69	48	202	150
Amortization to net income (loss) of net prior service credit	(6)	(2)	(17)	(13)
Impact of curtailment				(69)
Income taxes on pension and other postretirement benefit plans	(3)		(6)	10
Other			(4)
Comprehensive income (loss)	641	(78)	1,504	(11,173)
Comprehensive income attributable to noncontrolling interests	12	9	37	24
Comprehensive income (loss) attributable to Schlumberger	$ 629	$ (87)	$ 1,467	$ (11,197)