Accounts Payable and Accrued Liabilities, Current Accounts payable and accrued liabilities Accounts Payable and Accrued Liabilities [Member] Accounts Payable and Accrued Liabilities Estimated liability for taxes on income Less: Accumulated depreciation Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss) Adjustments to Additional Paid in Capital, Tax Effect from Share-based Compensation Tax benefits on stock options Receivables, allowance for doubtful accounts Amendment Flag Amortization expense charged to income Amount of Dilutive Securities, Stock Options and Restrictive Stock Units Assumed exercise of stock options Number of outstanding options to purchase shares of Schlumberger common stock which were not included in the computation of diluted earnings per share Net assets purchased during the period, excluding net assets acquired in business combinations. Acquisitions Assets Assets, Total ASSETS Assets, Current Assets, Current, Total Current Assets Balance Sheet Location [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition [Axis] Purchase price Purchase price Business Acquisition, Cost of Acquired Entity, Shares Distributed Under merger agreement, common stock shares issuable Business Acquisition, Cost of Acquired Entity, Stock Per Share Under merger agreement, shares of Schlumberger in exchange for each Smith share Business Acquisition, Purchase Price Allocation, Current Assets, Cash and Cash Equivalents Cash Business Acquisition, Purchase Price Allocation, Debt Assumed Net debt assumed Business Acquisition, Purchase Price Allocation, Deferred Income Tax Liabilities Deferred tax liabilities Deferred tax liabilities Business Acquisition, Purchase Price Allocation, Goodwill Amount Goodwill Business Acquisition, Purchase Price Allocation, Intangible Assets Business Acquisition, Purchase Price Allocation, Intangible Assets Intangible assets Business Acquisition, Purchase Price Allocation, Noncurrent Liabilities, Long-term Debt Long-term debt Business Acquisition, Purchase Price Allocation, Other Assets Business Acquisition, Purchase Price Allocation, Other Assets Other assets Business Acquisition, Purchase Price Allocation, Other Noncurrent Liabilities Other liabilities Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment Fixed assets Merger with Smith International, Inc. Business Combination Business Combination, Preliminary Allocation of the Purchase Price Disclosure [Text Block] Business Combination, Preliminary Allocation of the Purchase Price Disclosure Cash Cash and Cash Equivalents, at Carrying Value Cash, end of period Cash, beginning of period Net (decrease) increase in cash before translation effect Net (decrease) increase in cash before translation effect Amount charged against earnings in the period relating to items of an unusual nature. Charges, net of tax Charges Charges Amount charged against earnings in the period relating to items of an unusual nature, pretax. Charges, pretax Recorded pretax charges Amount charged against earnings in the period relating to items of an unusual nature, tax. Charges, tax Commercial Paper Commodity Contract Dividends declared, per share Common Stock Issued Common stock Components of Consolidated Income Taxes Components of Consolidated Income Taxes Components of net deferred tax assets Components of net deferred tax assets Total comprehensive income Total comprehensive income Comprehensive income 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. Contingencies Conversion Of Convertible Debentures Into Cash, Value Debentures redeemed for cash The number of common stock shares issued upon the conversion of convertible debentures. Shares of common stock converted from debentures Value of conversion of convertible debentures into common stock. Debentures converted into common shares Convertible debentures 2.125% Series B Convertible Debentures due June 1, 2023, outstanding Corporate and Other [Member] Corporate and Other Cost of revenue Cost of Sales Expenses Current Federal Tax Expense (Benefit) United States - Federal Current Fiscal Year End Date Current Foreign Tax Expense (Benefit) Outside United States Current Income Tax Expense (Benefit) Current Income Tax Expense (Benefit), Total Current: Current State and Local Tax Expense (Benefit) United States - State Customer Relationships Debt Disclosure [Text Block] Long-term Debt Debt Instrument [Axis] Long-term debt, carrying amount Notes relating to interest rate swap Long-term debt, fair value Debt Instrument, Name [Domain] Debt, Other Debt, Other Deferred Federal Income Tax Expense (Benefit) United States - Federal Deferred Foreign Income Tax Expense (Benefit) Outside United States Deferred income taxes Deferred income taxes Deferred: Deferred State and Local Income Tax Expense (Benefit) United States - State Deferred tax assets, valuation allowances relating to a capital loss carryforward, expires in 2010 Deferred Tax Assets, Intangible Assets Deferred Tax Assets, Intangible Assets Intangible assets Deferred Tax Assets, Multiclient Seismic Data Deferred Tax Assets, Multiclient Seismic Data Multiclient seismic data Deferred Tax Assets, Net Deferred Tax Assets, Net, Total Deferred Tax Assets, Net, Current Deferred taxes Deferred Tax Assets, Net, Noncurrent Deferred Taxes Deferred tax assets, valuation allowances relating to net operating losses in certain countries Other, net Deferred tax assets, foreign tax credit carryforward, expires in 2012 Postretirement benefits, net Amortization of net loss Amortization of net loss Amortization of prior service cost Contributions to defined benefit pension plans Expected return on plan assets Expected return on plan assets Interest cost on accumulated postretirement benefit obligation Interest cost on projected benefit obligation Defined Benefit Plan, Net Periodic Benefit Cost Defined Benefit Plan, Net Periodic Benefit Cost, Total Defined Benefit Plan, Net Periodic Benefit Cost before Curtailments Defined Benefit Plan, Net Periodic Benefit Cost before Curtailments Defined Benefit Plan, Net Periodic Benefit Cost before Curtailments, Total Curtailment charge Curtailment charge Defined Benefit Plans Disclosures, Defined Benefit Plans [Axis] Defined Benefit Plans [Domain] Service cost-benefits earned during period Depreciation expense relating to fixed assets Depreciation and amortization Fair value of derivatives assets designated as hedges Derivative assets Fair value of derivatives assets not designated as hedges Derivative Assets Designated as Hedging Instruments [Abstract] Derivative Assets Designated as Hedging Instruments [Abstract] Derivative designated as hedges: Derivative Assets Not Designated as Hedging Instruments [Abstract] Derivative Assets Not Designated as Hedging Instruments [Abstract] Derivative not designated as hedges: Derivative Contract Type [Domain] Derivative Asset, Fair Value Derivative Asset, Fair Value, Total Derivative Liability, Fair Value Derivative Liability, Fair Value, Total Derivative Instruments and Hedging Activities Derivative Instruments, Gain (Loss) by Derivative Instrument Risk [Axis] Derivative Instruments, Gain (Loss) by Hedging Relationship [Axis] Derivative Instruments, Gain (Loss) by Income Statement Location [Axis] Gain (loss) reclassified from accumulated OCI into income Gain/(loss) recognized in income Gain/(loss) recognized in OCI Derivative Liabilities Designated as Hedging Instruments [Abstract] Derivative Liabilities Designated as Hedging Instruments [Abstract] Derivative designated as hedges: Derivative Liabilities Not Designated as Hedging Instruments [Abstract] Derivative Liabilities Not Designated as Hedging Instruments [Abstract] Derivative not designated as hedges: Fair value of derivatives liabilities designated as hedges Derivative Liabilities Fair value of derivatives liabilities not designated as hedges Derivatives, by Derivative Instrument Contract [Axis] Derivatives, by Derivative Instrument Contract [Axis] Derivatives, by Derivative Instrument Contract [Domain] Derivatives, by Derivative Instrument Contract [Domain] Derivatives, Fair Value, by Balance Sheet Location [Axis] Derivatives, Fair Value, by Derivative Instrument Risk [Axis] Derivative Swap interest rate Developed Technology Rights Dilutive Securities Assumed conversion of debentures Disclosure - Acquisitions - Additional Information [Abstract] Disclosure - Acquisitions - Additional Information [Abstract] Disclosure - Amortization Expense Charged to Income [Abstract] Disclosure - Amortization Expense Charged to Income [Abstract] Disclosure - Change in the Carrying Amount of Multiclient Seismic Data [Abstract] Disclosure - Change in the Carrying Amount of Multiclient Seismic Data [Abstract] Disclosure - Changes in the Carrying Amount of Goodwill by Business Segment [Abstract] Disclosure - Changes in the Carrying Amount of Goodwill by Business Segment [Abstract] Disclosure - Charges - Additional Information [Abstract] Disclosure - Charges - Additional Information [Abstract] Disclosure - Common Stock Which Was Not Included in the Computation of Diluted Earnings Per Share [Abstract] Disclosure - Common Stock Which Was Not Included in the Computation of Diluted Earnings Per Share [Abstract] Disclosure - Components of Consolidated Taxes on Income [Abstract] Disclosure - Components of Consolidated Taxes on Income [Abstract] Disclosure - Components of Net Deferred Tax Assets [Abstract] Disclosure - Components of Net Deferred Tax Assets [Abstract] Disclosure - Depreciation Expense Relating to Fixed Assets [Abstract] Disclosure - Depreciation Expense Relating to Fixed Assets [Abstract] Disclosure - Derivative Instruments and Hedging Activities - Additional Information [Abstract] Disclosure - Derivative Instruments and Hedging Activities - Additional Information [Abstract] Disclosure - Effect of Derivative Instruments Designated as Fair Value Hedges and Not Designated as Hedges on the Consolidated Statement of Income [Abstract] Disclosure - Effect of Derivative Instruments Designated as Fair Value Hedges and Not Designated as Hedges on the Consolidated Statement of Income [Abstract] Disclosure - Effect of Derivative Instruments in Cash Flow Hedging Relationships on Income and Other Comprehensive Income [Abstract] Disclosure - Effect of Derivative Instruments in Cash Flow Hedging Relationships on Income and Other Comprehensive Income [Abstract] Disclosure - Fair Values of Outstanding Derivative Instruments [Abstract] Disclosure - Fair Values of Outstanding Derivative Instruments [Abstract] Disclosure - Gross Book Value and Accumulated Amortization of Intangible Assets [Abstract] Disclosure - Gross Book Value and Accumulated Amortization of Intangible Assets [Abstract] Disclosure - Income from Continuing Operations Before Taxes Which Were Subject to US and Non-US Income Taxes [Abstract] Disclosure - Income from Continuing Operations Before Taxes Which Were Subject to US and Non-US Income Taxes [Abstract] Disclosure - Income Tax - Additional Information [Abstract] Disclosure - Income Tax - Additional Information [Abstract] Disclosure - Intangible Assets - Additional Information [Abstract] Disclosure - Intangible Assets - Additional Information [Abstract] Disclosure - Long-term Debt - Additional Information [Abstract] Disclosure - Long-term Debt - Additional Information [Abstract] Disclosure - Merger with Smith International, Inc. - Additional Information [Abstract] Disclosure - Merger with Smith International, Inc. - Additional Information [Abstract] Disclosure - Net Pension Cost for the Schlumberger Pension Plans [Abstract] Disclosure - Net Pension Cost for the Schlumberger Pension Plans [Abstract] Disclosure - Net Periodic Benefit Cost for the Schlumberger US Postretirement Medical Plan [Abstract] Disclosure - Net Periodic Benefit Cost for the Schlumberger US Postretirement Medical Plan [Abstract] Disclosure - Pension and Other Postretirement Benefits - Additional Durational Information [Abstract] Disclosure - Pension and Other Postretirement Benefits - Additional Durational Information [Abstract] Disclosure - Purchase Price Allocated to Net Assets Acquired Upon Estimated Fair Values [Abstract] Disclosure - Purchase Price Allocated to Net Assets Acquired Upon Estimated Fair Values [Abstract] Disclosure - Reconciliation of Earnings Per Share [Abstract] Disclosure - Reconciliation of Earnings Per Share [Abstract] Disclosure - Reconciliation of the US Statutory Federal Tax Rate to the Consolidated Effective Income Tax Rate [Abstract] Disclosure - Reconciliation of the US Statutory Federal Tax Rate to the Consolidated Effective Income Tax Rate [Abstract] Disclosure - Schlumberger Operates Two Business Segments - Oilfield Services and WesternGeco [Abstract] Disclosure - Schlumberger Operates Two Business Segments - Oilfield Services and WesternGeco [Abstract] Disclosure - Summary of Charges [Abstract] Disclosure - Summary of Charges [Abstract] Disclosure - Summary of Fixed Assets [Abstract] Disclosure - Summary of Fixed Assets [Abstract] Disclosure - Summary of Inventory [Abstract] Disclosure - Summary of Inventory [Abstract] Disclosure - Summary of Other Long-Term Debt [Abstract] Disclosure - Summary of Other Long-Term Debt [Abstract] Dividends declared ($0.42 per share) Dividends declared ($0.42 per share) Dividend payable Document - Document and Entity Information [Abstract] Document - Document and Entity Information [Abstract] Document Fiscal Period Focus Document Fiscal Year Focus Document Period End Date Document Type Earnings Per Share [Abstract] Earnings per Share Earnings Per Share, Basic Net Income Basic Basic earnings per share of Schlumberger: Diluted Net Income Diluted earnings per share of Schlumberger: Earnings Per Share [Text Block] Earnings Per Share Effective income tax rate Effective income tax rate The United States federal statutory tax rate applicable under enacted tax laws to the Company's pretax income from continuing operations for the period. The "statutory" tax rate shall be the regular tax rate if there are alternative tax systems. US federal statutory rate US statutory federal tax rate Effect of equity method investment Non-US income taxed at different rates Charges (See Note 3) Other Translation effect on cash Employee Severance Entity Central Index Key Entity Common Stock, Shares Outstanding Entity [Domain] Entity Filer Category Entity Registrant Name Equity Component [Domain] Europe, CIS, and Africa Europe, CIS, and Africa Excess Tax Benefit from Share-based Compensation, Financing Activities Tax benefits on stock options Fair value adjustment, hedging, carrying amount Fair value adjustment-hedging Fair Value Hedging Accumulated Amortization Weighted average amortization period for all intangible assets (years) Fixed rate debt Fixed rate debt aggregate, after taking into account the effects of the interest rate swaps Fixed Rate Debt [Member] Fixed Rate Debt 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 Foreign Exchange Contract Foreign Pension Plans, Defined Benefit The amount of amortization expense expected to be recognized during the remainder of the year. Estimated amortization charged to income, remainder of 2010 Estimated amortization charged to income, 2015 Estimated amortization charged to income, 2014 Estimated amortization charged to income, 2011 Estimated amortization charged to income, 2013 Estimated amortization charged to income, 2012 General & administrative Geoservices [Member] Geoservices Goodwill Ending Balance Beginning Balance Additions Goodwill by Segment [Axis] This block of text may be used to disclose all or part of the information related to goodwill. Goodwill Disclosure [Text Block] Goodwill Goodwill, Segment [Domain] Impact of change in exchange rates Guaranteed Bonds 4 Point 50 Percent Due 2014 [Member] 4.50% Guaranteed Bonds due 2014 5.875% Guaranteed Bonds due 2011 [Member] 5.875% Guaranteed Bonds due 2011 3.00% Guaranteed Notes due 2013 [Member] 3.00% Guaranteed Notes due 2013 5.25% Guaranteed Notes due 2013 [Member] 5.25% Guaranteed Notes due 2013 Hedging Relationship [Domain] Fixed Income Investments, held to maturity Income (Loss) from Continuing Operations before Income Taxes and Minority Interest Income (Loss) from Continuing Operations before Income Taxes and Minority Interest Income (Loss) from Continuing Operations before Income Taxes and Minority Interest, Total Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Cumulative Effects of Changes in Accounting Principles, Noncontrolling Interest Income before taxes The portion of earnings (loss) from continuing operations before income taxes that is attributable to foreign operations, which is defined as income (loss) generated from operations located outside the United States. Income (Loss) from Continuing Operations before Income Taxes, Non United States Outside United States The portion of earnings (loss) from continuing operations before income taxes that is attributable to United States operations. Income (Loss) from Continuing Operations before Income Taxes, United States United States Earnings of companies carried at equity, less dividends received Earnings of companies carried at equity, less dividends received Income Statement [Abstract] Income Statement and Other Comprehensive Income Location [Domain] Income Tax Disclosure Table. Income Tax Disclosure Table Income Tax Taxes on income Consolidated taxes on income Decrease in accounts payable and accrued liabilities Increase (decrease) in estimated liability for taxes on income Decrease (increase) in inventories Decrease (increase) in inventories Change in assets and liabilities: Other-net Other-net Decrease in other liabilities Pension and other postretirement benefits expense (Increase) decrease in receivables (Increase) decrease in receivables The net change in the beginning and end of period Other Current Assets balances. Decrease (increase) in other current assets Decrease (increase) in other current assets Incremental Common Shares Attributable to Call Options and Warrants Assumed exercise of stock options Incremental Common Shares Attributable to Conversion of Debt Securities Assumed conversion of debentures Incremental Common Shares Attributable to Nonvested Shares with Forfeitable Dividends Unvested restricted stock Intangible Assets by Major Class [Axis] Intangible Assets by Major Class [Axis] Intangible Assets Disclosure [Text Block] Intangible Assets Intangible assets, estimated useful life Intangible assets amortized over a weighted average period Intangible Assets, Gross (Excluding Goodwill) Gross Book Value Intangible Assets, Major Class Name [Domain] Intangible Assets, Major Class Name [Domain] Net Book Value Intangible Assets Interest Interest Expense 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. Interest & other income, net Interest Income Interest Rate Contract Inventory Disclosure Table Inventory Disclosure Table Inventory Finished goods Inventories Inventories Raw materials & field materials Work in process Investments in Affiliated Companies Latin America Latin America Legal Entity [Axis] Liabilities Liabilities, Total Liabilities and Stockholders' Equity Liabilities and Stockholders' Equity, Total LIABILITIES AND EQUITY Liabilities, Current Liabilities, Current, Total Current Liabilities Long-term debt-current portion Long-term Debt [Text Block] Long-term Debt Short-term investments and Fixed income investments, held to maturity Medicare Part D Subsidy [Member] Medicare Part D Subsidy Merger & integration Middle East and Asia [Member] Middle East and Asia Stockholders' Equity Attributable to Noncontrolling Interest Noncontrolling interests Acquisition of noncontrolling interests Capitalized costs directly incurred in acquiring and processing of seismic surveys that are licensed on a nonexclusive basis, net of amortization. Multiclient Seismic Data Ending Balance Beginning Balance Multiclient Seismic Data, Capitalized in period Capitalized in period Capitalized in period Multiclient Seismic Data, Charged to cost of goods sold and services Charged to cost of revenue Disclosure of the carrying amount of multiclient seismic data based on completed and in-process seismic surveys. Multiclient Seismic Data Table Disclosure of the carrying amount of multiclient seismic data based on completed and in-process seismic surveys. Multiclient Seismic Data [Text Block] Multiclient Seismic Data NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES Cash flows from financing activities: NET CASH USED BY INVESTING ACTIVITIES NET CASH USED BY INVESTING ACTIVITIES Cash flows from investing activities: NET CASH PROVIDED BY OPERATING ACTIVITIES NET CASH PROVIDED BY OPERATING ACTIVITIES Cash flows from operating activities: Adjustments to reconcile net income to cash provided by operating activities: Net Income attributable to Schlumberger Net Income attributable to Schlumberger Net Income Net income (loss) allocated to unvested restricted stock Net income (loss) allocated to unvested restricted stock Unvested restricted stock Net income attributable to noncontrolling interests Net income attributable to noncontrolling interests Schlumberger amounts attributable to: Net Income (Loss) Available to Common Stockholders, Basic Basic Net Income (Loss) Available to Common Stockholders, Diluted Diluted Noncontrolling Interests Nondesignated North America North America 6.50% Notes due 2012 [Member] 6.50% Notes due 2012 Notes to Financial Statements [Abstract] Notes to Financial Statements [Abstract] Contracts outstanding in various foreign currencies (US dollar equivalent) Notional amount of interest rate swap Oilfield Services [Member] Oilfield Services Basis of Presentation Other Assets, Current Other current assets Other Assets Other Assets, Noncurrent Other Assets Deferred employee benefits liabilities Changes in fair value of derivatives Currency translation adjustments Other Current Assets [Member] Other Current Assets Other Intangible Assets [Member] Other Intangible Assets Other Liabilities Other Liabilities, Noncurrent Other Liabilities Other Long-term Debt, Noncurrent Other Long-term Debt, Noncurrent, Total Long-term Debt Other non-cash items Other business acquisitions and investments, net of cash acquired Other business acquisitions and investments, net of cash acquired Other Postretirement Benefits Disclosure Other Postretirement Benefits Disclosure Other Regions Other Regions Outside United States [Member] Outside United States Parent Company [Member] The net cash outflow from capitalized costs directly incurred in acquiring and processing of seismic surveys that are licensed on a nonexclusive basis. Multiclient seismic data capitalized Sale (purchase) of investments, net Sale (purchase) of investments, net Payments for (Proceeds from) Other Investing Activities Other Payments for Repurchase of Equity Stock repurchase program Dividends paid Dividends paid Acquisitions and minority interest investments, net of cash acquired Acquisition of Geoservices, net of cash acquired Acquisition of Geoservices, net of cash acquired Capital expenditures Capital expenditures Pension and other postretirement benefits funding Pension and other postretirement benefits funding Pension and other postretirement benefits curtailment charge Pension and Other Postretirement Benefits Postretirement Benefits Pension Disclosure Pension Disclosure Postretirement benefits curtailment [Member] Postretirement benefits curtailment Proceeds from issuance of long-term debt Net decrease in short-term borrowings Proceeds from exercise of stock options Proceeds from employee stock purchase plan Net Income Net Income Net Income Property, Plant and Equipment Disclosure [Text Block] Fixed Assets Property, plant & equipment Fixed Assets less accumulated depreciation Fixed Assets less accumulated depreciation Property, Plant and Equipment Receivables less allowance for doubtful accounts (2010-$141; 2009-$160) Reconciliation of Earnings Per Share Reconciliation of Earnings Per Share Reconciliation of the US Statutory Federal Tax Rate Reconciliation of the US Statutory Federal Tax Rate Disclosure of profit or loss, total assets for each reportable region, and a description of the types of products and services for each reportable region. Region Reporting Information, by Region [Axis] Repayment of long-term debt Repayment of long-term debt A regional component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements. Reporting Region [Domain] Reporting Segment [Domain] Research & engineering Research and Development Expense [Member] Research and Development Expense Restructuring and Related Activities Disclosure [Text Block] Charges Restructuring and Related Cost, by Type of Restructuring [Axis] Retained Earnings (Accumulated Deficit) Retained earnings Retained Earnings Revenues Revenue Schedule of Amortization Expense Schedule of Amortization Expense Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share Schedule of Depreciation Expense Schedule of Depreciation Expense Schedule of Derivative Instruments, Effect on Income and Other Comprehensive Income Schedule of Derivative Instruments, Effect on Income and Other Comprehensive Income Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance Schedule of Derivative Instruments in Statement of Financial Position, Fair Value Schedule of Goodwill Schedule of Intangible Assets by Major Class Schedule of Intangible Assets by Major Class Schedule of Restructuring and Related Costs Schedule of Segment Reporting Information, by Segment Segment Information Segment Reporting Information, by Segment [Axis] Income before taxes Interest expense included in the segment results Interest income included in the segment results Segment Reporting Information, Revenue Revenue 2.125% Series B Convertible Debentures due June 1, 2023 [Member] 2.125% Series B Convertible Debentures due June 1, 2023 Stock-based compensation expense Number of shares of stock held by shareholders. Shares, Outstanding Ending Balance Beginning Balance Short-term borrowings Short-term investments Smith International Incorporate [Member] Smith International Incorporate Software Statement, Equity Components [Axis] Statement [Line Items] Statement of Cash Flows [Abstract] Statement of Financial Position [Abstract] Statement of Stockholders' Equity [Abstract] Statement [Table] Shares granted to Directors Schlumberger stockholders' equity Schlumberger stockholders' equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Ending Balance Beginning Balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest, Total Equity Stockholders' Equity, Other Other Shares issued on conversion of debebtures Stock Issued During Period, Shares, Employee Stock Purchase Plans Shares issued under employee stock purchase plan Stock Issued During Period, Shares, Stock Options Exercised Shares sold to optionees, less shares exchanged Shares issued on conversion of debentures Stock Issued During Period, Value, Employee Stock Purchase Plan Shares issued under employee stock purchase plan Vesting of restricted stock Stock-based compensation cost Stock Issued During Period, Value, Stock Options Exercised Shares sold to optionees, less shares exchanged Trading Symbol Common Stock In Treasury Stock repurchase plan Treasury stock Treasury stock Stock repurchase program Stock repurchase program Type of Restructuring [Domain] United States [Member] United States United States Pension Plans of US Entity, Defined Benefit United States Postretirement Benefit Plans of US Entity, Defined Benefit Valuation allowance Valuation allowance Variable rate debt Variable rate debt aggregate, after taking into account the effects of the interest rate swaps Assuming dilution Assuming dilution Average shares outstanding: Weighted Average Number of Shares Outstanding, Basic Basic WesternGeco [Member] WesternGeco