Statement [Table] Statement [Line Items] Document Type Document Period End Date Document Fiscal Year Focus Document Fiscal Period Focus Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date Entity Filer Category Entity Common Stock, Shares Outstanding CONSOLIDATED STATEMENT OF INCOME [Abstract] Revenues Revenues, Total Revenue Interest Income and Other Interest and other income, net Interest and other income, net Interest & other income Includes operating interest income earned as part of a core business activity, equity income representing the undistributed income or loss of investments which are accounted for under the equity method of accounting, and other miscellaneous income or loss earned from core business activities. Costs and Expenses [Abstract] Expense Research & engineering Research and Development Expense, Total Research & engineering General & administrative General and Administrative Expense, Total General & administrative Income Loss from Continuing Operations Before Income Taxes Minority Interest and Income Loss from Equity Method Investments Income from continuing operations before taxes Income before taxes Taxes on Income Consolidated taxes on income Taxes on income Net income Profit Loss Net income Net income Net Income Loss Attributable to Noncontrolling Interest Net Income Loss Net Income attributable to Schlumberger Net income Earnings Per Share Basic Net Income Net income Net Income Diluted Net Income Net income Net Income Average shares outstanding: Average shares outstanding [Abstract] Weighted Average shares outstanding Weighted Average Number of Shares Outstanding Basic Weighted Average Number of Shares Outstanding, Basic, Total Basic Assuming dilution Diluted Assuming dilution CONSOLIDATED BALANCE SHEET [Abstract] Assets [Abstract] ASSETS ASSETS Assets Current [Abstract] Current Assets Cash Cash Short-term investments Short-term Investments, Total Short-term investments Receivables, Net, Current Receivables, Net, Current, Total Receivables less allowance for doubtful accounts (2011 - $177; 2010 - $185) Inventories Inventories Deferred Tax Assets Net Current Deferred Tax Assets, Net, Current, Total Deferred taxes Other Assets Current Other current assets Assets Current Current Assets Total Fixed Income Investments, held to maturity Fixed income investments, held to maturity Fixed Income Investments, held to maturity Investments in Affiliated Companies Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures, Total Investments in Affiliated Companies Fixed Assets Less Accumulated Depreciation Property, Plant and Equipment, Net, Ending Balance Property, Plant and Equipment, Net, Beginning Balance Fixed Assets less accumulated depreciation by geographic area Fixed assets less accumulated depreciation Multiclient Seismic Data Balance at end of year Balance at beginning of year Multiclient seismic data Capitalized costs directly incurred in acquiring and processing of seismic surveys that are licensed on a nonexclusive basis, net of amortization. Balance, December 31, 2010 Goodwill Balance at December 31, 2011 Balance at January 1, 2011 Balance, January 1, 2010 Goodwill, Total Net Book Value Intangible Assets Intangible Assets, Net (Excluding Goodwill), Total Other Assets Noncurrent Other Assets Assets Assets Total Assets Liabilities and Stockholders Equity [Abstract] LIABILITIES AND EQUITY Liabilities Current [Abstract] Current Liabilities Accounts Payable and Accrued Liabilities Current Accounts payable and accrued liabilities Accounts payable and accrued liabilities Estimated liability for taxes on income Estimated liability for taxes on income Commercial paper borrowings Long-term debt-current portion Long-term Debt, Current Maturities, Total Long-term debt - current portion Short-term borrowings Short-term Borrowings, Total Short-term borrowings Liabilities Current Current Liabilities Total Other Long-term Debt, Noncurrent Other Long-term Debt, Noncurrent, Total Long-term Debt Postretirement Benefits Postretirement Benefits Postretirement Benefits Deferred Tax Liabilities Noncurrent Deferred Taxes Deferred Taxes Other Liabilities Noncurrent Other Liabilities Liabilities Total Liabilities Liabilities, Total Stockholders Equity Including Portion Attributable To Noncontrolling Interest [Abstract] Equity Common stock Common Stock, Value, Issued, Total Common stock Treasury Stock Value Treasury stock Retained Earnings Accumulated Deficit Retained earnings Accumulated Other Comprehensive Loss Accumulated Other Comprehensive Income (Loss), Net of Tax, Ending Balance Accumulated Other Comprehensive Income (Loss), Net of Tax, Beginning Balance Accumulated other comprehensive loss Accumulated other comprehensive loss Stockholders' Equity Schlumberger stockholders' equity Minority Interest Noncontrolling interests Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Ending Balance Beginning Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Total Liabilities And Stockholders' Equity Liabilities and stockholders' equity, Total Receivables, Allowance for Doubtful Accounts Balance at end of year Balance at beginning of year Allowance for doubtful accounts on receivable CONSOLIDATED STATEMENT OF CASH FLOWS [Abstract] Net Cash Provided by Used in Operating Activities [Abstract] Cash flows from operating activities: Adjustments to reconcile net income to net cash provided by operating activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Depreciation and Amortization Depreciation and amortization Depreciation, Depletion and Amortization, Total Depreciation and amortization Income Loss From Equity Method Investments Net of Dividends or Distributions Earnings of companies carried at equity, less dividends received Income (Loss) from Equity Method Investments, Net of Dividends or Distributions, Total Earnings of companies carried at equity, less dividends received Deferred income taxes Deferred income taxes Deferred income taxes Share-based Compensation Share-based Compensation, Total Stock-based compensation expense Pension and other postretirement benefits expense Pension and other postretirement benefits expense Increase (Decrease) in Pension and Postretirement Obligations, Total Pension and other postretirement benefits expense Pension and Other Postretirement Benefit Contributions Pension and other postretirement benefits funding Pension and other postretirement benefits funding Increase Decrease in Operating Capital [Abstract] Change in operating assets and liabilities: Increase Decrease in Receivables (Increase) decrease in receivables Increase (Decrease) in Receivables, Total (increase) decrease in receivables Increase Decrease in Inventories (Increase) decrease in inventories Increase (Decrease) in Inventories, Total Increase in inventories Increase (decrease) in accounts payable and accrued liabilities Increase Decrease in accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities, Total (Decrease) increase in estimated liability for taxes on income (Decrease) increase in estimated liability for taxes on income Increase Decrease In Other Operating Liabilities (Decrease) increase in other liabilities Increase (Decrease) in Other Operating Liabilities, Total Increase Decrease in Other Operating Capital Net Net Cash Provided by Used in Operating Activities NET CASH PROVIDED BY OPERATING ACTIVITIES Net Cash Provided by Used in Investing Activities [Abstract] Cash flows from investing activities: Payments to Acquire Property Plant And Equipment Capital expenditures Capital expenditures Payments to Acquire Property, Plant, and Equipment, Total Capital expenditures Payments for Proceeds from Capitalized Costs Support Equipment and Facilities Multiclient seismic data capitalized Multiclient seismic data capitalized The net cash outflow from capitalized costs directly incurred in acquiring and processing of seismic surveys that are licensed on a nonexclusive basis. Sale (purchase) of investments, net Payments for Proceeds from Investments Payments for (Proceeds from) Investments, Total Sale (purchase) of investments, net Payments for Proceeds from Other Investing Activities Other Other Other Net Cash Provided by Used in Investing Activities NET CASH USED IN INVESTING ACTIVITIES Net Cash Provided by Used in Financing Activities [Abstract] Cash flows from financing activities: Payments of Dividends Dividends paid Payments of Dividends, Total Dividends paid Proceeds from employee stock purchase plan Proceeds from employee stock purchase plan Proceeds from exercise of stock options Proceeds from exercise of stock options Payments for Repurchase of Equity Stock repurchase program Payments for Repurchase of Equity, Total Stock repurchase program Proceeds from issuance of long-term debt Proceeds from Issuance of Long-term Debt, Total Proceeds from issuance of long-term debt Repayments of Long Term Debt Repayment of long-term debt Repayments of Long-term Debt, Total Repayment of long-term debt Net decrease increase in short-term borrowings Net decrease in short-term borrowings Net Cash Provided by Used in Financing Activities NET CASH USED IN FINANCING ACTIVITIES Net (decrease) increase in cash before translation effect Cash and Cash Equivalents Period Increase Decrease Net increase (decrease) increase in cash before translation effect Translation effect on cash Effect of Exchange Rate on Cash and Cash Equivalents, Total Translation effect on cash Cash and Cash Equivalents at Carrying Value Cash, end of period Cash, beginning of period Cash and Cash Equivalents, at Carrying Value, Total CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY [Abstract] Statement, Equity Components [Axis] Equity Component [Domain] Common Stock [Member] Common Stock Issued Treasury Stock [Member] Common Stock In Treasury Retained Earnings [Member] Retained Earnings Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Loss Noncontrolling Interests [Member] Noncontrolling Interests Currency translation adjustments Currency translation adjustments Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax, Total Currency translation adjustments Changes in fair value of derivatives Changes in fair value of derivatives Other Comprehensive Income, Derivatives Qualifying as Hedges, Net of Tax, Total Changes in fair value of derivatives Shares sold to optionees less shares exchanged Stock Issued During Period Value Stock Options Exercised Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures Vesting of restricted stock Stock Issued During Period Value Employee Stock Purchase Plan Shares issued under employee stock purchase plan Treasury Stock Value Acquired, Cost Method Stock repurchase program Stock Issued During Period, Value, Share-based Compensation Stock-based compensation cost Shares issued on conversions of debentures Stock Issued During Period, Value, Conversion of Convertible Securities Stockholders' Equity, Other Other Dividends, Cash Dividends declared Dividends, Cash, Total Shares sold to optionees less shares exchanged, in Shares Stock Issued During Period, Shares, Stock Options Exercised Exercised, shares Shares issued under employee stock purchase plan, in Shares Stock Issued During Period, Shares, Employee Stock Purchase Plans Stock repurchase program, in Shares Treasury Stock, Shares, Acquired Stock repurchase program, in shares Dividends declared, per share Dividends declared, per share Restructuring and Related Activities Disclosure [Text Block] Charges and Credits Inventory Disclosure [Text Block] Inventory Property, Plant and Equipment Disclosure [Text Block] Fixed Assets Multiclient Seismic Data [Text Block] Multiclient Seismic Data Disclosure of the carrying amount of multiclient seismic data based on completed and in-process seismic surveys. Intangible Assets Disclosure [Text Block] Intangible Assets Derivative Instruments and Hedging Activities Disclosure [Text Block] Derivative Instruments and Hedging Activities Long-term Debt [Text Block] Long-term Debt and Debt Facility Agreements Income Tax Disclosure [Text Block] Income Tax Segment Reporting Disclosure [Text Block] Segment Information Pension and Other Postretirement Benefits Disclosure [Text Block] Pension and Other Benefit Plans Property, Plant and Equipment [Table Text Block] Property, Plant and Equipment Schedule of Goodwill [Table Text Block] Schedule of Goodwill Schedule of Derivative Instruments in Statement of Financial Position, Fair Value Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Text Block] Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Text Block] Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance Schedule of Segment Reporting Information, by Segment Schedule of Segment Reporting Information, by Segment [Text Block] Debt Instrument [Axis] Debt Instrument, Name [Domain] Type of Restructuring [Domain] Medicare Part D Subsidy [Member] Medicare part D subsidy. Medicare Part D Subsidy [Member] Debt Instrument, Face Amount Notes relating to interest rate swap Guaranteed notes face amount Guaranteed Notes Five Point Two Five Percent Due Two Thousand Thirteen [Member] 5.25% Guaranteed Notes due 2013 [Member] Guaranteed notes five point two five percent due two thousand thirteen. Guaranteed Notes Three Point Zero Zero Percent Due Two Thousand Thirteen [Member] 3.00% Guaranteed Notes due 2013 [Member] Guaranteed notes three point zero zero percent due two thousand thirteen. Commercial Paper [Member] Commercial Paper [Member] Commercial paper borrowings [Member] Debt, Other [Member] Debt, Other [Member] Other variable rate debt [Member] Debt, other. Schlumberger amounts attributable to [Abstract] Schlumberger Income from continuing operations Schlumberger amounts attributable to: Dilutive Securities Dilutive Securities, Total Assumed conversion of debentures Net Income (Loss) Available to Common Stockholders, Diluted Diluted Diluted Incremental Common Shares Attributable to Call Options and Warrants Assumed exercise of stock options Incremental Common Shares Attributable to Nonvested Shares with Forfeitable Dividends Unvested restricted stock Payments to Acquire Businesses and Interest in Affiliates Acquisitions and minority interest investments, net of cash acquired Senior Notes Eight Point Six Two Five Due Two Thousand Fourteen [Member] 8.625% Senior Notes due 2014 [Member] Senior notes eight point six two five due two thousand fourteen. Senior Notes Six Point Zero Zero Due Two Thousand Sixteen [Member] 6.00% Senior Notes due 2016 [Member] Senior notes six point zero zero due two thousand sixteen. Senior Notes Nine Point Seven Five Due Two Thousand Nineteen [Member] 9.75% Senior Notes due 2019 [Member] Senior notes nine point seven five due two thousand nineteen. Tradenames [Member] Tradenames [Member] Customer Relationships [Member] Customer Relationships [Member] Finite Lived Intangible Assets Weighted Average Useful Life Weighted Average Amortization Period for all Intangible Assets (Years) Finite-Lived Intangible Assets, Weighted-Average Useful Life, Total weighted-average life in years Inventory, Net [Abstract] Inventory Raw Materials & Field Materials Inventory, Raw Materials and Supplies, Total Raw materials & field materials Work in Process Work in process Finished Goods Finished goods Property, Plant and Equipment, Net, by Type [Abstract] Property, Plant and Equipment Property, Plant & Equipment Property, Plant and Equipment, Gross, Ending Balance Property, Plant and Equipment, Gross, Beginning Balance Property, plant and equipment Less: Accumulated Depreciation Less: Accumulated depreciation Less: Accumulated depreciation Depreciation Expense Relating to Fixed Assets Depreciation, Total Depreciation expense relating to fixed assets Change in Carrying Amount of Multiclient Seismic Data [Abstract] Multiclient Seismic Data Change in the carrying amount of multiclient seismic data. Multiclient Seismic Data Capitalized in Period Multiclient seismic data, capitalized in period. Capitalized in year Multiclient Seismic Data Charged to Cost of Goods Sold and Services Charged to expense Multiclient seismic data, charged to cost of goods sold and services. Goodwill [Roll Forward] Schedule of Goodwill Oilfield Services [Member] Oilfield Services [Member] Oilfield services. Goodwill Translation And Purchase Accounting Adjustments Impact of changes in exchange rates Goodwill, Translation and Purchase Accounting Adjustments, Total Impact of changes in exchange rates Intangible Assets, Net (Excluding Goodwill) [Abstract] Gross book value and accumulated amortization of intangible assets Intangible Assets by Major Class [Axis] Intangible Assets by Major Class. Intangible Assets, Major Class Name [Domain] Intangible assets, major class name. Technology/Technical Know-How [Member] Technology/Technical Know-How [Member] Intangible Assets Gross Excluding Goodwill Intangible assets, gross (excluding goodwill) Gross Book Value Accumulated Amortization Accumulated Amortization Estimated amortization charged to income, 2011 Estimated amortization charged to income, 2012 Estimated amortization charged to income, 2012 Estimated amortization charged to income, 2013 Estimated amortization charged to income, 2013 Estimated amortization charged to income, 2014 Estimated amortization charged to income, 2014 Estimated amortization charged to income, 2015 Estimated amortization charged to income, 2015 Estimated amortization charged to income, 2016 Derivatives, by Derivative Instrument Contract [Axis] Derivatives, by derivative instrument contract. Derivatives, by Derivative Instrument Contract [Domain] Derivatives, by derivative instrument contract. Fixed Rate Debt [Member] Fixed Rate Debt [Member] Fixed rate debt. Floating Rate Debt [Member] Floating Rate Debt [Member] Floating rate debt. Recognized a Cumulative Net Gain in Equity Relating to Revaluation of Foreign Currency Forward Contracts and Foreign Currency Options Designated as Cash Flow Hedges Recognized a cumulative net gain in Equity relating to revaluation of foreign currency forward contracts and foreign currency options designated as cash flow hedges Notional Amount of Foreign Currency Derivatives Contracts outstanding in various foreign currencies (US dollar equivalent) Fixed Rate Debt Fixed rate debt. Fixed rate debt aggregate, after taking into account the effects of the interest rate swaps Variable Rate Debt Variable rate debt aggregate, after taking into account the effects of the interest rate swaps Variable rate debt. Notional Amount of Interest Rate Derivatives Notional amount of interest rate swap