Derivative Instruments and Hedging Activities - Additional Information (Detail)	6 Months Ended
	Jun. 30, 2015 USD ($) Country	Dec. 31, 2014	Dec. 31, 2013 EUR (€)
Derivative [Line Items]
Fixed rate debt aggregate, after taking into account the effects of the interest rate swaps	$ 8,900,000,000
Variable rate debt aggregate, after taking into account the effects of the interest rate swaps	4,400,000,000
Short-term investments and fixed income investments, held to maturity	4,200,000,000
Recognized a cumulative net (loss) in Accumulated other comprehensive loss relating to revaluation of foreign currency forward contracts and foreign currency options designated as cash flow hedges	$ (66,000,000)
Minimum
Derivative [Line Items]
Number of countries in which Schlumberger conducts business | Country	85
1.50% Guaranteed Notes due 2019
Derivative [Line Items]
Guaranteed notes face amount | €			€ 500,000,000
Cross currency swap
Derivative [Line Items]
Notional amount of interest rate swap | €			€ 500,000,000
Fixed Rate Debt | 1.50% Guaranteed Notes due 2019
Derivative [Line Items]
Derivative swap interest rate			1.50%
Floating Rate Debt | 1.50% Guaranteed Notes due 2019
Derivative [Line Items]
Floating interest rate on securities	three-month LIBOR plus approximately 64 basis points
Foreign exchange contracts
Derivative [Line Items]
Notional amount of interest rate swap	$ 6,000,000,000
Foreign exchange contracts | Debt | Derivatives designated as hedges
Derivative [Line Items]
Notional amount of interest rate swap	$ 2,500,000,000
London Interbank Offered Rate (LIBOR) | Floating Rate Debt | 1.50% Guaranteed Notes due 2019
Derivative [Line Items]
Basis point		0.64%