Long-term Debt and Debt Facility Agreements - Additional Information (Detail) (USD $)	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011
Proforma Debt Instrument [Line Items]
Investment in subsidiary-Schlumberger Investment SA	100.00%
Committed debt facility agreement aggregated	$ 4,100,000,000
Unused debt facility	3,800,000,000
Weighted average interest rate on variable rate debt	3.60%
Long-term Debt maturity in 2014	1,657,000,000
Long-term Debt maturity in 2015	1,318,000,000
Long-term Debt maturity in 2016	1,843,000,000
Long-term Debt maturity in 2017	999,000,000
Long-term Debt maturity in 2021	2,694,000,000
Long-term Debt maturity in 2022	998,000,000
Long-term debt, fair value	9,900,000,000	8,900,000,000
Commercial paper [Member]
Proforma Debt Instrument [Line Items]
Committed debt facility agreement aggregated	3,500,000,000
Commercial paper borrowings		900,000,000
Commercial paper programs mature in December 2013 [Member]
Proforma Debt Instrument [Line Items]
Committed debt facility agreement aggregated	500,000,000
Commercial paper programs mature in July 2016 [Member]
Proforma Debt Instrument [Line Items]
Committed debt facility agreement aggregated	$ 3,000,000,000

Long Term Debt Maturities Repayments Of Principal In Year Nine

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- Definition

Long Term Debt Maturities Repayments Of Principal In Year Thereafter

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No definition available.

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- Definition

Weighted average interest rate on variable rate debt.

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No definition available.

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- Definition

This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

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The number of units or percentage investment held in the subsidiary by the limited liability company or limited partnership.

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-Name Regulation S-X (SX)

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