Statement [Table] Legal Entity [Axis] Entity [Domain] Parent Company [Member] 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 Amendment Flag 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 & other income, net 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. Gain Loss On Investments Gain on investment in M-I SWACO Expenses Cost of revenue Cost of Goods and Services Sold, Total Cost of revenue Research & engineering Research and Development Expense, Total Research & engineering General & administrative General and Administrative Expense, Total General & administrative Interest Interest Interest Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments Income from Continuing Operations before taxes Income from Continuing Operations before taxes Income before taxes Taxes on income Consolidated taxes on income Taxes on income Profit Loss Net income Net Income Net Income Net Income Loss Attributable To Noncontrolling Interest Net income attributable to noncontrolling interests Net income attributable to noncontrolling interests Net income attributable to noncontrolling interests Net Income Loss Net Income attributable to Schlumberger Net Income Earnings Per Share Basic Net Income Net Income Basic earnings per share of Schlumberger Diluted Net Income Net Income Diluted earnings per share of Schlumberger Average shares outstanding Average shares outstanding Weighted Average Number Of Shares Outstanding Basic Weighted Average Number of Shares Outstanding, Basic, Total Basic Assuming dilution Assuming dilution CONSOLIDATED BALANCE SHEET [Abstract] Assets Abstract ASSETS ASSETS Current Assets 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 (2010-$185; 2009-$160) Inventories Inventories Deferred Tax Assets Net Current Deferred Tax Assets, Net, Current, Total Deferred taxes Other Assets Current Other current assets Other current assets Assets Current Assets, Current, Total Assets, Current, Total Total current assets 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 Multiclient Seismic Data Balance at end of year Balance at beginning of year Capitalized costs directly incurred in acquiring and processing of seismic surveys that are licensed on a nonexclusive basis, net of amortization. Goodwill Ending Balance Beginning Balance Net Book Value Intangible Assets Intangible Assets, Net (Excluding Goodwill), Total Deferred Tax Assets Net Noncurrent Deferred Tax Assets, Net, Noncurrent, Total Deferred Taxes Other Assets Noncurrent Other Assets Other Assets Assets Assets Assets, Total LIABILITIES AND EQUITY LIABILITIES AND EQUITY Current Liabilities 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 Dividend payable Dividend payable Long-term debt-current portion Commercial paper borrowings Long-term Debt, Current Maturities, Total Long-term debt - current portion Short-term borrowings Short-term Borrowings, Total Short-term borrowings Convertible debentures Convertible debentures Liabilities Current Liabilities, Current, Total Liabilities, Current, Total Total current liabilities Other Long-term Debt, Noncurrent Other Long-term Debt Other Long-term Debt, Noncurrent, Total Long-term Debt Postretirement Benefits Postretirement Benefits Deferred Tax Liabilities Noncurrent Deferred Taxes Deferred Taxes Other Liabilities Noncurrent Other Liabilities Other Liabilities Liabilities Liabilities, Total Equity 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 Stockholders' Equity Attributable to Parent, Ending Balance Stockholders' Equity Attributable to Parent, Beginning Balance Schlumberger stockholders' equity Schlumberger stockholders' equity Minority Interest Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance Noncontrolling interests 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 Recievables, allowance for doubtful accounts Allowance for Doubtful Accounts Receivable, Current, Ending Balance Allowance for Doubtful Accounts Receivable, Current, Beginning Balance Allowance for doubful accounts on receivable CONSOLIDATED STATEMENT OF CASH FLOWS [Abstract] Cash flows from operating activities: Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: 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 Stock-based compensation expense Share-based Compensation, Total Stock-based compensation expense Pension and other postretirement benefits curtailment charge Pension and other postretirement benefits curtailment charge Pension and Other Postretirement Benefit Expense, Total Pension and other postretirement benefits curtailment charge 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 Other non-cash items Other non-cash items Change in operating assets and liabilities: Change in operating assets and liabilities: Increase Decrease In Receivables (Increase) decrease in receivables Increase (Decrease) in Receivables, Total Decrease (increase) in receivables Increase Decrease In Inventories (Increase) decrease in inventories Increase (Decrease) in Inventories, Total Increase in inventories Increase Decrease Other Current Assets Decrease (increase) in other current assets Decrease (increase) in other current assets Increase in other current assets The net change in the beginning and end of period Other Current Assets balances. Increase Decrease in accounts payable and accrued liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities, Total (Decrease) increase in accounts payable and accrued liabilities (Decrease) increase in estimated liability for taxes on income Increase (decrease) in estimated liability for taxes on income Increase Decrease In Other Operating Liabilities (Decrease) increase in other liabilities Increase Decrease In Other Operating Capital Net Other--net Other--net Other-net Net Cash Provided By Used In Operating Activities NET CASH PROVIDED BY OPERATING ACTIVITIES Cash flows from investing activities: 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. Payments To Acquire Businesses Net Of Cash Acquired Acquisition of Eastern Echo, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired, Total Acquisition of Geoservices, net of cash acquired Other Payments To Acquire Businesses Other business acquisitions and investments, net of cash acquired Other business acquisitions and investments, net of cash acquired Payments For Proceeds From Investments Sale (purchase) of investments, net 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 Cash flows from financing activities: 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 Excess Tax Benefit From Share Based Compensation Financing Activities Tax benefits on 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) increase in short-term borrowings Net (decrease) increase in short-term borrowings Net Cash Provided By Used In Financing Activities NET CASH USED IN FINANCING ACTIVITIES Cash And Cash Equivalents Period Increase Decrease Net increase (decrease) 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 Issued Common Stock In Treasury Retained Earnings Accumulated Other Comprehensive Income (Loss) Noncontrolling Interests Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Comprehensive income: 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 Deferred employee benefits liabilities Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax, Total Deferred employee benefits liabilities Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Total comprehensive income Total comprehensive income Stock Issued During Period Value Stock Options Exercised Shares sold to optionees less shares exchanged Stock Granted During Period, Value, Share-based Compensation Shares granted to Directors 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 Stock Issued During Period, Value, Conversion of Convertible Securities Shares issued on conversion of debentures Stock Issued During Period, Value, Acquisitions Acquisition of Smith International, Inc. Noncontrolling Interest, Period Increase (Decrease) Acquisition of noncontrolling interests Stockholders' Equity, Other Other Dividends, Cash Dividends declared ($0.84 per share) Adjustments to Additional Paid in Capital, Tax Effect from Share-based Compensation Tax benefits on stock options Shares Outstanding Ending Balance, in shares Beginning Balance, in shares Number of shares of stock held by shareholders. Stock Issued During Period, Shares, Acquisitions Acquisition of Smith International, Inc., in shares Acquisition of Smith International Inc. Stock Issued During Period, Shares, Stock Options Exercised Shares sold to optionees less shares exchanged, in shares Stock Issued During Period, Shares, Employee Stock Purchase Plans Shares issued under employee stock purchase plan, in shares Treasury Stock, Shares, Acquired Stock repurchase program, in shares Stock Issued During Period, Shares, Conversion of Convertible Securities Shares issued on conversion of debebtures Dividends declared, per share Dividends declared, per share Restructuring and Related Activities Disclosure [Text Block] Charges and Credits Asset Purchase Disclosure [Text Block] Acquisitions Net assets purchased during the period, excluding net assets acquired in business combinations. 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. Goodwill Disclosure [Text Block] Goodwill This block of text may be used to disclose all or part of the information related to goodwill. Intangible Assets Disclosure [Text Block] Intangible Assets Derivative Instruments and Hedging Activities Disclosure [Text Block] Derivative Instruments and Hedging Activities Debt Disclosure [Text Block] Long-term Debt and Debt Facility Agreements Income Tax Disclosure [Text Block] Income Taxes Contingencies Disclosure [Text Block] Contingencies Describes any existing condition, situation, or set of circumstances involving uncertainty as of the balance sheet date (or prior to issuance of the financial statements) as to a probable or reasonably possible gain or loss incurred by an entity and typically discloses the amount of range of possible gain or loss recorded. Segment Reporting Disclosure [Text Block] Segment Information Pension and Other Postretirement Benefits Disclosure [Text Block] Pension and Other Benefit Plans Summary Of Charges And Credits [Text Block] Summary Of Charges And Credits Summary Of Charges And Credits. Schedule Of Charges Related To Workforce Reductions [Text Block] Schedule of charges related to workforce reductions Schedule Of Charges Related To Workforce Reductions [Text Block] Reconciliation of Earnings Per Share [Text Block] Reconciliation of Earnings Per Share Reconciliation of earnings per share. Schedule Of Fair Value Of Consideration Transferred To Effect Merger With Smith [Text Block] Fair Value of the Consideration Transferred to Effect the Merger With Smith Schedule of Fair Value of the Consideration Transferred to Effect the Merger With Smith [Text Block] Business Combination Preliminary Allocation Of Purchase Price Disclosure [Text Block] Business Combination, Preliminary Allocation of the Purchase Price Disclosure Business Combination, Preliminary Allocation of the Purchase Price Disclosure [Text Block] Schedule of Business Acquisitions, by Acquisition [Text Block] Preliminary Estimates of the Fair Value of Identifiable Assets Acquired and Liabilities Assumed Business Acquisition, Pro Forma Information [Text Block] Consolidated Supplementary Pro Forma Statement of Operation Schedule of Earnings Per Share, Diluted, by Common Class [Text Block] Charges and Credits Included in the Pro Forma Net Income Attributable to Schlumberger and Diluted Earnings Per Share Inventory Disclosure Table [Text Block] Inventory Disclosure Table Inventory Disclosure Table. Property, Plant and Equipment [Text Block] Property, Plant and Equipment Multiclient Seismic Data Table [Text Block] Multiclient Seismic Data Table Disclosure of the carrying amount of multiclient seismic data based on completed and in-process seismic surveys. Schedule of Goodwill [Text Block] Schedule of Goodwill Schedule Of Intangible Assets By Major Class [Text Block] Schedule of Intangible Assets by Major Class Schedule of Intangible Assets by Major Class Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Text Block] Schedule of Derivative Instruments in Statement of Financial Position, Fair Value 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 Derivative Instruments, Effect on Income and Other Comprehensive Income [Text Block] Schedule of Derivative Instruments, Effect on Income and Other Comprehensive Income Schedule of Derivative Instruments, Effect on Income and Other Comprehensive Income Long-term Debt [Text Block] Long-term Debt Income Tax Disclosure Table [Text Block] Income Tax Disclosure Table Income Tax Disclosure Table. Components Of Net Deferred Tax Assets [Text Block] Components of Net Deferred Tax Assets Components of net deferred tax assets Components Of Consolidated Income Taxes [Text Block] Components of Consolidated Income Taxes Components of Consolidated Income Taxes Reconciliation Of United States Statutory Federal Tax Rate [Text Block] Reconciliation of the US Statutory Federal Tax Rate Reconciliation of the US Statutory Federal Tax Rate Schedule of Segment Reporting Information, by Segment [Text Block] Financial Information Pension Disclosure [Text Block] Net pension cost for the Schlumberger pension plans Pension Disclosure Segment Reporting Information, by Segment [Axis] Reporting Segment [Domain] M-I SWACO [Member] M-I SWACO. Debt Instrument [Axis] Debt Instrument, Name [Domain] 6.50% Notes due 2012 [Member] 6.50% Notes due 2012 [Member] Restructuring and Related Cost, by Type of Restructuring [Axis] Type of Restructuring [Domain] Medicare Part D Subsidy [Member] Medicare Part D Subsidy [Member] Medicare Part D Subsidy [Member] Employee Severance [Member] Charges, pretax Charges, pretax Recorded pretax charges Charges, pretax Amount charged against earnings in the period relating to items of an unusual nature, pretax.