Document and Entity Information [Abstract] Document and Entity Information. Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Document Fiscal Year Focus Document Fiscal Period Focus Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Public Float Entity Common Stock, Shares Outstanding Consolidated Statement of Operations [Abstract] Statement [Table] Statement, Business Segments [Axis] Segment, Business [Domain] Williams Partners [Member] Williams Partners Williams Partners. Exploration Production [Member] Exploration & Production Exploration Production. Midstream Canada And Olefins [Member] Midstream Canada & Olefins Midstream canada and olefins. Others [Member] Other segment [member] Other Other. Business Intersegment Eliminations [Member] Business Intersegment Eliminations Intercompany Eliminations General Corporate Expense [Member] General Corporate Expense General Corporate Expense. Statement [Line Items] Revenues: Revenues [Abstract] Revenues Total revenues Gas management revenue Segment costs and expenses: Costs and Expenses [Abstract] Costs And Operating Expenses Costs and operating expenses Costs and operating expenses. Selling, general, and administrative expenses Selling, General and Administrative Expense, Total Selling, General and Administrative Expense Other Operating Income Expense Net Other (income) expense - net Other Operating Income Expense Net. Total Segment Costs Expenses Total segment costs and expenses Total segment costs and expenses. Operating income (loss): Operating Income (Loss) [Abstract] Operating Income (Loss) Segment operating income (loss) Total operating income (loss) Total operating income Interest accrued Interest and Debt Expense, Total Interest accrued Interest and Debt Expense Interest capitalized Interest capitalized Interest Costs, Capitalized During Period Investing Income Net Investing Income - net Investing income (loss) including equity earnings. Other income (expense) - net Other income (expense) - net Other Nonoperating Income (Expense) Income Loss From Continuing Operations Before Income Taxes Income (loss) from continuing operations before income taxes Income (loss) from continuing operations before income taxes. Total provision (benefit) Provision (benefit) for income taxes Income Tax Expense (Benefit) Income (loss) from continuing operations Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest, Total Income (loss) from continuing operations Income (Loss) from Continuing Operations, Including Portion Attributable to Noncontrolling Interest Income related to discontinued operations Income (loss) from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Net income (loss) Net income (loss) Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Less: Net income attributable to noncontrolling interests Less: Net income attributable to noncontrolling interests Net Income (Loss) Attributable to Noncontrolling Interest Net income Net income (loss) attributable to The Williams Companies, Inc. Net income (loss) Net Income (Loss) Attributable to Parent Amounts attributable to The Williams Companies, Inc.: Income Amounts Attributable to Parent, Disclosures [Abstract] Income (loss) from continuing operations Income (loss) from continuing operations attributable to The Williams Companies, Inc. available to common stockholders for basic and diluted earnings (loss) per common share Income (Loss) from Continuing Operations Attributable to Parent Attributable to The Williams Companies, Inc. Income (loss) from discontinued operations Attributable to The Williams Companies, Inc. Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent Basic earnings (loss) per common share: Earnings (loss) per common share from continuing operations: Earnings Per Share, Basic [Abstract] Income (loss) from continuing operations Income (Loss) from Continuing Operations, Per Outstanding Share, Total Basic Income (Loss) from Continuing Operations, Per Basic Share Income (loss) from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Per Basic Share Net income Net income (loss) Earnings Per Share, Basic Weighted-average shares (thousands) Weighted-average shares (thousands) Basic weighted-average shares Weighted Average Number of Shares Outstanding, Basic Diluted earnings (loss) per common share: Earnings Per Share, Diluted [Abstract] Income (loss) from continuing operations Diluted Income (Loss) from Continuing Operations, Per Diluted Share Income (loss) from discontinued operations Income (Loss) from Discontinued Operations, Net of Tax, Per Diluted Share Net income Net income (loss) Earnings Per Share, Diluted Weighted-average shares (thousands) Weighted-average shares (thousands) Diluted weighted-average shares Weighted Average Number of Shares Outstanding, Diluted Cash dividends declared per common share Common Stock, Dividends, Per Share, Declared Consolidated Balance Sheet [Abstract] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value, Total Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash and Cash Equivalents, at Carrying Value Accounts, Notes, Loans and Financing Receivable, Net, Current Accounts, Notes, Loans and Financing Receivable, Net, Current, Total Accounts and notes receivable (net of allowance of $18 at March 31, 2011 and $15 at December 31,2010) Inventories Inventories, Total Inventory, Net Current Derivative Assets Derivative assets Current gross derivative assets. These are not presented net per master netting arrangements. Other current assets and deferred charges Other Assets, Current Total current assets Assets, Current, Total Assets, Current Investments Total investments Long-term Investments Property, plant, and equipment, at cost Total property, plant, and equipment, at cost Property, plant, and equipment - at cost Property, Plant and Equipment, Gross, Beginning Balance Property, Plant and Equipment, Gross, Ending Balance Property, Plant and Equipment, Gross Accumulated depreciation, depletion and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Property, plant and equipment - net Property, plant, and equipment - net Property, Plant and Equipment, Net, Beginning Balance Property, Plant and Equipment, Net, Ending Balance Property, Plant and Equipment, Net Non Current Derivative Assets Derivative assets Noncurrent gross derivative assets. These are not presented net per master netting arrangements. Other assets and deferred charges Other assets and deferred charges Other Assets, Noncurrent Total assets Assets LIABILITIES AND EQUITY Liabilities [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current, Total Accounts Payable, Current Accrued liabilities Accrued Liabilities, Current, Total Accrued Liabilities, Current Current Derivative Liabilities Derivative liabilities Current gross derivative liabilities. These are not presented net per master netting arrangements. Long-term debt due within one year Long-term debt due within one year Long-term debt due within one year Debt, Current Total current liabilities Liabilities, Current, Total Liabilities, Current Long-term debt Long-term debt Secured Capital lease obligations Long-term Debt and Capital Lease Obligations Deferred income taxes Deferred Tax Liabilities, Noncurrent Noncurrent Derivative Liabilities Derivative liabilities Noncurrent gross derivative liabilities. These are not presented net per master netting arrangements. Deferred Credits And Other Liabilities Non Current Other liabilities and deferred income Deferred credits and other liabilities non-current. Contingent liabilities and commitments (Note 11) Commitments and Contingencies Equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Common stock (960 million shares authorized at $1 par value; 622 million shares issued at March 31, 2011, and 620 million shares issued at December 31, 2010) Common Stock, Value, Issued, Total Common Stock, Value, Issued, Beginning Balance Common Stock, Value, Issued, Ending Balance Common Stock, Value, Issued Capital in excess of par value Additional Paid in Capital, Common Stock, Beginning Balance Additional Paid in Capital, Common Stock, Ending Balance Additional Paid in Capital, Common Stock Retained earnings (deficit) Retained Earnings (Accumulated Deficit), Total Retained Earnings (Accumulated Deficit), Beginning Balance Retained Earnings (Accumulated Deficit), Ending Balance Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax, Total Total, Beginning Balance Total, Ending Balance Accumulated Other Comprehensive Income (Loss), Net of Tax Treasury stock, at cost (35 million shares of common stock) Treasury Stock, Value, Beginning Balance Treasury Stock, Value, Ending Balance Treasury stock, at cost (35 million shares of common stock) Treasury Stock, Value Total stockholders' equity Stockholders' Equity Attributable to Parent, Total Stockholders' Equity Attributable to Parent, Beginning Balance Stockholders' Equity Attributable to Parent, Ending Balance Stockholders' Equity Attributable to Parent Noncontrolling interests in consolidated subsidiaries Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance Stockholders' Equity Attributable to Noncontrolling Interest Total equity Beginning balance Ending balance Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and equity Liabilities and Stockholders' Equity Allowance for doubtful accounts, current Allowance for Doubtful Accounts Receivable, Current, Beginning Balance Allowance for Doubtful Accounts Receivable, Current, Ending Balance Allowance for Doubtful Accounts Receivable, Current Common stock, par value Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued, Total Common Stock, Shares, Issued Treasury Stock, at cost Treasury Stock, Shares, Beginning Balance Treasury Stock, Shares, Ending Balance Treasury Stock, Shares Consolidated Statement of Changes in Equity [Abstract] Statement, Equity Components [Axis] Equity Component [Domain] Parent [Member] The Williams Companies,Inc Noncontrolling Interests [Member] Noncontrolling Interests Comprehensive income (loss): Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest [Abstract] Other Comprehensive Income (Loss), Net of Tax [Abstract] Other comprehensive income (loss), net of tax: Net change in cash flow hedges Cash Flow Hedges, Other Comprehensive Income, Net of Tax Other Comprehensive Income, Derivatives Qualifying as Hedges, Net of Tax Foreign currency translation adjustments Foreign Currency Translation, Other Comprehensive Income, Net of Tax Foreign Currency Exchange gains included in Other (income) expense Other Comprehensive Income, Foreign Currency Transaction and Translation Adjustment, Net of Tax Pension and other postretirement benefits - net Other Comprehensive Income, Defined Benefit Plans Adjustment, Net of Tax Total comprehensive income (loss) Total other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Total comprehensive income (loss) Total other comprehensive income Comprehensive Income, Net of Tax, Including Portion Attributable to Noncontrolling Interest Cash dividends - common stock Dividends, Common Stock, Cash Dividends and distributions to noncontrolling interests Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders Allocated Share Based Compensation Expense Net Of Tax Stock-based compensation, net of tax Allocated Share Based Compensation Expense NetOf Tax. Consolidation Less Than Wholly Owned Subsidiary Parent Ownnership Interest Changes Net Change in Williams Partners L.P. ownership interest (Note 2) Change in Williams Partners L.P. ownership interest (Note 2) Consolidation Less Than Wholly Owned Subsidiary Parent Ownnership Interest Changes Net. Consolidated Statement of Cash Flows [Abstract] OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Depreciation, depletion and amortization Depreciation, Depletion and Amortization, Total Depreciation, depletion and amortization expense for property, plant, and equipment Depreciation, depletion and amortization Depreciation, Depletion and Amortization Provision (benefit) for deferred income taxes Total Deferred Income Tax Expense (Benefit) Provision for loss on investments, property and other assets Asset Impairment Charges, Total Asset impairment charges Asset Impairment Charges Amortization of stock-based awards Share-based Compensation, Total Total stock-based compensation expense Share-based Compensation Cash provided (used) by changes in current assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts and notes receivable Accounts and notes receivable Increase (Decrease) in Accounts and Notes Receivable Inventories Increase (Decrease) in Inventories, Total Inventories Increase (Decrease) in Inventories Other current assets and deferred charges Other current assets and deferred charges Increase (Decrease) in Other Operating Assets Accounts payable Increase (Decrease) in Accounts Payable, Total Increase (Decrease) in Accounts Payable Accrued liabilities Increase (Decrease) in Accrued Liabilities, Total Increase (Decrease) in Accrued Liabilities Changes in current and noncurrent derivative assets and liabilities Changes in current and noncurrent derivative assets and liabilities Increase (Decrease) in Commodity Contract Assets and Liabilities Other, including changes in noncurrent assets and liabilities Other, including changes in noncurrent assets and liabilities Increase (Decrease) in Other Operating Assets and Liabilities, Net Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from long-term debt Proceeds from Issuance of Long-term Debt, Total Proceeds from Issuance of Long-term Debt Payments of long-term debt Repayments of Long-term Debt, Total Payments of long-term debt Repayments of Long-term Debt Dividends paid Dividends paid Payments of Dividends, Common Stock Dividends and distributions paid to noncontrolling interests Dividends and distributions paid to noncontrolling interests Payments of Dividends, Noncontrolling Interest Payments for debt issuance costs Payments for debt issuance costs Payments of Debt Issuance Costs Premiums Paid On Early Debt Retirements And Tender Offer Premiums paid on early debt retirements Cash premiums included in early debt retirement costs Premiums paid on early debt retirements Premiums paid on early debt retirements and tender offer. Changes in cash overdrafts Proceeds from (Repayments of) Bank Overdrafts Other - net Proceeds from (Payments for) Other Financing Activities Net cash provided (used) by financing activities Net Cash Provided by (Used in) Financing Activities INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities [Abstract] Capital expenditures Capital expenditures Capital expenditures Capital expenditures Payments to Acquire Productive Assets Purchases of investments/advances to affiliates Payments to Acquire Investments, Total Cash paid to contribute investment in Gulfstream Purchases of investments/advances to affiliates Payments to Acquire Investments Other - net Other - net Payments for (Proceeds from) Other Investing Activities Net cash used by investing activities Net Cash Provided by (Used in) Investing Activities Increase (decrease) in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease), Total Cash and Cash Equivalents, Period Increase (Decrease) Increases to property, plant and equipment Property, Plant and Equipment, Additions Changes In Accounts Payable And Accrued Liabilities Changes in related accounts payable and accrued liabilities Changes in accounts payable and accrued liabilities related to property, plant and equipment. Changes in related accounts payable and accrued liabilities Changes in related accounts payable and accrued liabilities Changes in related accounts payable and accrued liabilities General [Abstract] General. General [Text Block] General General. Basis of Presentation [Abstract] Basis of Presentation Organization Consolidation And Presentation Of Financial Statements Disclosure [Text Block] Schedule of Disposal Groups, Including Discontinued Operations, Income Statement, Balance Sheet and Additional Disclosures [Text Block] Summarized Results of Discontinued Operations Provision (Benefit) for Income Taxes [Abstract] Provision (Benefit) for Income Taxes Income Tax Disclosure [Text Block] Earnings (loss) per common share from continuing operations: Earnings (Loss) Per Common Share from Continuing Operations [Abstract] Earnings (Loss) Per Common Share from Continuing Operations Earnings Per Share [Text Block] Employee Benefit Plans [Abstract] Employee Benefit Plans Pension and Other Postretirement Benefits Disclosure [Text Block] Inventories Inventories [Abstract] Inventories Inventory Disclosure [Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures. Financial Instruments, Derivatives, Guarantees and Concentration of Credit Risk [Abstract] Financial Instruments, Derivatives, Guarantees and Concentration Of Credit Risk. Financial Instruments Derivatives Guarantees And Concentration Of Credit Risk [Text Block] Financial Instruments, Derivatives, Guarantees, and Concentration of Credit Risk Text block for footnote Financial Instruments, Derivatives, Guarantees and Concentration of Credit Risk. Contingent Liabilities Contingent Liabilities Commitments and Contingencies Disclosure [Text Block] Segment Reporting [Abstract] Segment Reporting. Segment Disclosures Segment Reporting Disclosure [Text Block] Schedule of Earnings Per Share Reconciliation [Table Text Block] Earnings (loss) per common share from continuing operations Schedule of Earnings Per Share Reconciliation Table Text Block. Components of net periodic benefit expense Defined Benefit Plan, Net Periodic Benefit Cost [Abstract] Schedule Of Net Benefit Costs Table [Text Block] Net periodic benefit expense Schedule Of Net Benefit Costs Table Text Block. Schedule Of Inventory Current Table [Text Block] Inventories Schedule Of Inventory Current Table Text Block. Schedule Of Fair Value Assets And Liabilities Measured On Recurring Basis [Table Text Block] Fair value of assets and liabilities measured on recurring basis Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Fair Value Assets Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Text Block] Fair Value Measurements Using Significant Unobservable Inputs Fair Value Assets Liabilities Measured On Recurring Basis Unobservable Input Reconciliation. Financial Instruments Derivatives Guarantees and Concentration of Credit Risk (Tables) [Abstract] Financial instruments, derivatives, guarantees and concentration of credit risk. Carrying amounts and fair values of financial instruments Fair Value, by Balance Sheet Grouping [Text Block] Schedule Of Notional Amounts Of Outstanding Derivative Positions [Table Text Block] Notional quantities of the net long (short) positions in commodity derivatives portfolio Tabular disclosure of the notional amounts of outstanding derivative positions. Fair value of energy commodity derivatives Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Text Block] Pre-tax gains and losses for energy commodity derivatives designated as cash flow hedges, as recognized in accumulated other comprehensive income (loss) (AOCI), revenues or costs and operating expense Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Text Block] Schedule Of Other Derivatives Not Designated As Hedging Instruments Statements Of Financial Performance And Financial Position Location [Table Text Block] Pre-tax gains and losses for energy commodity derivatives not designated as hedging instruments Tabular disclosure for other derivative instruments not designated as hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position. Gross Credit Exposure From Derivative Contracts [Text Block] Gross credit exposure from derivative contracts Gross credit exposure from derivative contracts. Net Credit Exposure From Derivative Contracts [Text Block] Net credit exposure from derivative contracts Net credit exposure from derivative contracts. Segment Revenues Operating Profit Loss By Reporting Segment [Text Block] Reconciliation of segment revenues and segment profit (loss) Segment Revenues Operating Profit Loss By Reporting Segment Text Block. Basis of Presentation (Details) [Abstract] Basis of Presentation Details. Description of Business [Table] Description of Business [Table]. Description of Business [Axis] Description of Business [Axis]. Description of Business [Domain] Description of Business [Domain]. Transcontinental Gas Pipe Line Company, LLC [Member] Transcontinental Gas Pipe Line Company, LLC Transcontinental Gas Pipe Line Company, LLC [Member]. Northwest Pipeline GP [Member] Northwest Pipeline GP Northwest Pipeline GP [Member]. Gulfstream Natural Gas System LLC [Member] Gulfstream Natural Gas System LLC Gulfstream Natural Gas System LLC [Member]. Description of Business [Line Items] Description of Business [Line Items]. Basis of Presentation (Textuals) [Abstract] Basis of Presentation (Textuals) [Abstract] Basis of Presentation Textuals. Percent interest in Gulfstream Equity Method Investment, Ownership Percentage Ownership Interest Ownership interest in subsidiary Ownership Interest. Change between ownership interest and noncontrolling interests resulting from the restructuring Change between ownership interest and noncontrolling interests resulting from the restructuring Change between ownership interest and noncontrolling interests resulting from the restructuring. Overstatement of noncontrolling interests in consolidated subsidiaries Overstatement of noncontrolling interests in consolidated subsidiaries Overstatement of noncontrolling interests in consolidated subsidiaries. Understatement of capital in excess of par value Understatement of capital in excess of par value Understatement of capital in excess of par value. Decrease To Capital In Excess Of Par Value Due To Strategic Restructuring Decrease to capital in excess of par value due to strategic restructuring Decrease to capital in excess of par value due to strategic restructuring. Increase To Noncontrolling Interests In Consolidated Subsidiaries Due To Strategic Restructuring Increase to noncontrolling interests in consolidated subsidiaries due to strategic restructuring Increase to noncontrolling interests in consolidated subsidiaries due to strategic restructuring. Discontinued Operations (Details) [Abstract] Discontinued Operations. Summarized Results of Discontinued Operations [Abstract] Summarized Results of Discontinued Operations Summarized Results of Discontinued Operations. Revenues Disposal Group, Including Discontinued Operation, Revenue (Provision) benefit for income taxes (Provision) benefit for income taxes Discontinued Operation, Tax Effect of Discontinued Operation Asset Sales and Other Accruals (Details) [Abstract] Asset sales and other accruals. Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Line Items] Other Transaction Costs Other transaction costs Other Transaction Costs Attributable To Noncontrolling Interests Other transaction costs attributable to noncontrolling interests Accelerated Amortization Of Debt Costs Accelerated amortization of debt costs Accelerated amortization of debt costs related to amendments of credit facilities Provision (Benefit) for Income Taxes (Details) [Abstract] Provision Benefit For Income Taxes. Provision (benefit) for income taxes from continuing operations Income Tax Expense (Benefit), Continuing Operations [Abstract] Current : Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Foreign Foreign Current Foreign Tax Expense (Benefit) Total Current Income Tax Expense (Benefit) Deferred: Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Foreign Foreign Deferred Foreign Income Tax Expense (Benefit) Provision Benefit For Income Taxes (Textuals) [Abstract] Provision Benefit for Income Taxes (Textuals) [Abstract] Provision Benefit For Income Taxes. Tax benefit from settlements and revised assessment Tax Adjustments, Settlements, and Unusual Provisions Decrease in unrecognized tax benefits Unrecognized Tax Benefits, Decreases Resulting from Current Period Tax Positions Earnings (Loss) Per Common Share from Continuing Operations (Details) [Abstract] Earnings (Loss) Per Common Share from Continuing Operations (Details). Schedule of Earnings Per Share [Table] Schedule Of Earnings Per Share. Earnings Per Share [Axis] Earnings Per Share. Earnings Per Share [Domain] Earnings Per Share. Restricted Stock [Member] Nonvested Restricted Stock Units Stock Options [Member] Stock options Convertible Debt Securities [Member] Convertible debentures Earnings Per Share Table [Line Items] Earnings Loss Per Common Share from Continuing Operations [Abstract] Earnings (loss) per common share from continuing operations Earnings (Loss) Per Common Share from Continuing Operations Effect of dilutive securities: Weighted Average Number Diluted Shares Outstanding Adjustment [Abstract] Incremental common shares attributable to share-based payment arrangements under effects of dilutive securities item Incremental Common Shares Attributable to Share-based Payment Arrangements, Total Incremental Common Shares Attributable To Share Based Payment Arrangements Incremental dilutive shares, Convertible debt Incremental Common Shares Attributable To Conversion Of Debt Securities Earnings Per Share Basic And Diluted Abstract Earnings (loss) per common share from continuing operations: Earnings Per Share Basic And Diluted. Stock options excluded [Abstract] Stock options excluded Stock options excluded. Out of Money Options excluded from computation of earnings per share amount Options excluded Out of the Money Options excluded from computation of earnings per share amount. Weighted-average exercise price of options excluded Weighted-average exercise price of options excluded Weighted-average exercise price of options excluded. Exercise price ranges of options excluded, minimum Exercise price ranges of options excluded, minimum Exercise price ranges of options excluded, minimum. Exercise price ranges of options excluded, maximum Exercise price ranges of options excluded, maximum Exercise price ranges of options excluded, maximum. Current Quarter Weighted Average Market Price First quarter weighted-average market price Current quarter weighted average market price. Earnings (loss) per common share from continuing operations (Additional Textuals) [Abstract] Earnings (loss) per common share from continuing operations. Interest Expenses, net of tax Interest on Convertible Debt, Net of Tax Options excluded (millions) Number of weighted-average shares excluded from computation of diluted earnings per common share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Earnings Loss Per Common Share from Continuing Operations (Textuals) [Abstract] Earnings (loss) per common share from continuing operations (Textuals) [Abstract] Earnings (Loss) Per Common Share from Continuing Operations textuals. Threshold Of Income Loss From Continuing Operations Attributable To Company Available To Common Stockholders For Dilution Calculation Threshold of income loss from continuing operations attributable to company available to common stockholders for dilution calculation Threshold of income loss from continuing operations attributable to company available to common stockholders for dilution calculation. Employee Benefit Plans (Details) [Abstract] Employee Benefit Plans. Schedule of Defined Benefit Plans Disclosures [Table] Defined Benefit Plans Disclosures, Defined Benefit Plans [Axis] Defined Benefit Plans [Domain] Pension Plans Defined Benefit [Member] Pension Benefits Other Postretirement Benefit Plans Defined Benefit [Member] Other Postretirement Benefits Defined Benefit Plan Disclosure [Line Items] Net periodic benefit expense and other changes in plan assets and benefit obligations [Abstract] Net periodic benefit expense and other changes in plan assets and benefit obligations Net periodic benefit expense and other changes in plan assets and benefit obligations. Service cost Prior service credit Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on plan assets Expected return on plan assets Defined Benefit Plan, Expected Return on Plan Assets Amortization of prior service credit Amortization of prior service credit Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Defined Benefit Plan Amortization Of Net Gains Losses Amortization of net actuarial loss Amortization of net actuarial loss Amortization Defined Benefit Plan Amortization Of Gains Losses Amortization of net actuarial loss Net periodic benefit expense (income) Net periodic benefit expense (income) Defined Benefit Plan, Net Periodic Benefit Cost Employee Benefit Plans (Textuals) [Abstract] Employee Benefit Plans (Textuals) [Abstract] Employee Benefit Plans Textuals Abstract. Employer contributions under plan Defined Benefit Plan, Contributions by Employer Defined Benefit Plan Estimated Future Employer Contributions In Current Fiscal Year Additional contributions to plans anticipated for remainder of 2011 The employer's best estimate, as soon as it can be reasonably determined, of contributions expected to be paid to the plan in the current remaining fiscal period. Estimated contributions may be presented in the aggregate combining (1) contributions required by funding regulations or laws, (2) discretionary contributions, and (3) noncash contributions. Inventories (Details) [Abstract] Inventories. Natural gas liquids and olefins Energy Related Inventory, Natural Gas Liquids Natural gas in underground storage Energy Related Inventory, Natural Gas in Storage Materials, supplies, and other Other Inventory Fair Value Measurements (Details) [Abstract] Fair Value Measurements Details. Fair Value, Assets Measured on Recurring Basis [Table] Derivatives, Fair Value, by Balance Sheet Location [Axis] Balance Sheet Location [Domain] Energy Derivatives [Member] Energy Derivatives Energy Derivatives Member. Aro Trust Investments [Member] ARO Trust investments ARO Trust Investments Member. Fair Value, Assets Measured on Recurring Basis, Disclosure Items [Axis] Fair Value, Assets Measured on Recurring Basis, Disclosure Items [Domain] Fair Value Inputs Level 1 [Member] Level 1 Fair Value Inputs Level 2 [Member] Level 2 Fair Value Inputs Level 3 [Member] Level 3 Fair Value, Assets Measured on Recurring Basis, Financial Statement Captions [Line Items] Energy derivatives Fair Value, Assets Measured on Recurring Basis, Derivative Financial Instruments, Assets Fair Value, Liabilities Measured on Recurring Basis [Table] Fair Value, Liabilities Measured on Recurring Basis, Disclosure Items [Axis] Fair Value, Liabilities Measured on Recurring Basis, Disclosure Items [Domain] Fair Value, Liabilities Measured on Recurring Basis, Financial Statement Captions [Line Items] Energy derivatives Fair Value, Liabilities Measured on Recurring Basis, Derivative Financial Instruments, Liabilities Fair Value Measurements Using Significant Unobservable Inputs Fair Value, Assets and Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Abstract] Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Value Beginning balance Ending balance Fair value measurement with unobservable inputs reconciliation recurring basis asset liability value. Realized and unrealized gains losses [Abstract] Realized and unrealized gains (losses): Realized and unrealized gains losses. Fair Value Assets And Liabilities Measured On Recurring Basis Gain Loss Included In Earnings Included in income (loss) from continuing operations This item represents the amount of the total realized and unrealized gains or losses for the period which are included in the statement of income (or changes in net assets); the fair value of which assets and liabilities was or is measured on a recurring basis using significant unobservable inputs (Level 3). Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset And Liability Gain Loss Included In Other Comprehensive Income Loss Included in other comprehensive income (loss) This element represents total gains (losses) for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity). Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Settlements Settlements Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Liability Settlements. Transfers into Level 3 Transfers into Level 3 Transfers into Level 3. Transfers out of Level 3 Transfers out of Level 3 Transfers out of Level 3. Unrealized Gains Losses Included In Income Loss From Continuing Operations Relating To Instruments Held At Period End Unrealized gains (losses) included in income (loss) from continuing operations relating to instruments still held at March 31 Unrealized gains Losses Included In Income Loss From Continuing Operations Relating To Instruments Held At Period End. Fair Value Measurements (Textuals) [Abstract] Fair Value Measurements (Textuals) [Abstract] Fair Value Measurements Textuals Abstract. Tenure Of Expiry Of Derivatives Portfolio Tenure of expiry of derivatives portfolio (months) Tenure of expiry of derivatives portfolio. Percent of derivatives expiring Percent of derivatives expiring Percent of derivatives expiring. Financial Instruments Derivatives Guarantees and Concentration of Credit Risk (Details) [Abstract] Financial instruments, derivatives, guarantees and concentration of credit risk. Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Fair Value, Disclosure Item Amounts [Domain] Carrying Reported Amount Fair Value Disclosure [Member] Carrying Amount Estimate Of Fair Value Fair Value Disclosure [Member] Fair Value Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Carrying Amounts And Fair Values Of Financial Instruments [Abstract] Carrying amounts and fair values of financial instruments Carrying Amounts And Fair Values Of Financial Instruments. Asset And Liability [Abstract] Asset (Liability) Asset And Liability. Restricted cash (current and noncurrent) Restricted Cash and Cash Equivalents Asset Retirement Obligation Trust Investments ARO Trust Investments ARO Trust investments Asset retirement obligation trust investments. Long-term debt, including current portion Long-term Debt, Total Long-term Debt Guarantees, Fair Value Disclosure Guarantee Other Assets Liability Net Other Other assets liability net. Net energy derivatives [Abstract] Net energy derivatives: Net energy derivatives. Energy commodity cash flow hedges Cash Flow Hedges Derivative Instruments at Fair Value, Net, Total Cash Flow Hedges Derivative Instruments at Fair Value, Net Other energy derivatives Other Derivatives Not Designated as Hedging Instruments at Fair Value, Net, Total Other Derivatives Not Designated as Hedging Instruments at Fair Value, Net Options [Member] Options Options. Index [Member] Index Index. Basis [Member] Basis Basis. Central Hub Risk [Member] Central Hub Risk Central Hub Risk. Risks Inherent in Servicing Assets and Servicing Liabilities by Type of Risk [Axis] Risks Inherent in Servicing Assets and Servicing Liabilities, Type [Domain] Other Risk Management [Member] Other Risk Management Other Risk Management. Risk Management [Member] Risk Management Risk Management. Notional quantities of the net long short positions in commodity derivatives portfolio Abstract Notional quantities of the net long (short) positions in commodity derivatives portfolio Notional quantities of the net long (short) positions in commodity derivatives portfolio. Derivative Instruments Designated as Hedging Instruments Price Risk Cash Flow Hedges [Abstract] Net notional quantity of derivative designated As hedging instrument Nonmonetary Notional Amount of Price Risk Cash Flow Hedge Derivatives Derivative Instruments Not Designated as Hedging Instruments Price Risk Derivative Instruments Not Designated as Hedging Instruments [Abstract] Net notional quantity of price risk derivative instruments not designated as hedging instruments Nonmonetary Notional Amount of Price Risk Derivative Instruments Not Designated as Hedging Instruments Fair Values Derivatives Balance Sheet Location By Derivative Contract Type By Hedging Designation [Table] Derivative Instruments, Gain (Loss) by Derivative Instrument Risk [Axis] Derivative Contract Type [Domain] Legacy Natural Gas Contracts From Former Power Business [Member] Legacy natural gas contracts from former power business Legacy natural gas contracts from former power business. Other Contract Other Contract [Member] Derivatives Fair Value [Line Items] Fair Value Of Energy Commodity Derivatives [Abstract] Fair value of energy commodity derivatives Fair value of energy commodity derivatives. Designated as hedging instruments, assets Derivative Asset Designated as Hedging Instrument, Fair Value Designated as hedging instruments, liabilities Derivative Liability Designated as Hedging Instrument, Fair Value Not designated as hedging instruments, assets Derivative Asset Not Designated as Hedging Instrument, Fair Value Not designated as hedging instruments, liabilities Derivative Liability Not Designated as Hedging Instrument, Fair Value Total derivatives, assets Derivative Asset, Fair Value Total derivatives, liabilities Derivative Liability, Fair Value Pre Tax Gains And Losses For Energy Commodity Derivatives Designated As Cash Flow Hedges [Abstract] Pre-tax gains and losses for energy commodity derivatives designated as cash flow hedges, as recognized in accumulated other comprehensive income (loss) (AOCI) or revenues Pre-tax gains and losses for energy commodity derivatives flow hedges, as recognized in accumulated other comprehensive income (loss) (AOCI) or revenues. Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net, Total Net gain (loss) recognized in other comprehensive income (loss) (effective portion) Net gain (loss) reclassified from accumulated other comprehensive income (loss) into income (effective portion) Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net, Total Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net Gain (loss) recognized in income (ineffective portion) Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net, Total Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net Derivative Instruments Gain Loss By Hedging Relationship By Income Statement Location By Derivative Instrument Risk [Table] Concentration Risk by Benchmark [Axis] Concentration Risk Benchmark [Domain] Revenues [Member] Revenues Revenues. Costs and Operating Expenses [Member] Costs and operating expenses Costs and operating expenses Derivative Instruments Gain Loss [Line Items] Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net [Abstract] Pre-tax gains and losses for our energy commodity derivatives not designated as hedging instruments Net gain Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net, Total Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net Schedule of Credit Derivatives [Table] Credit Derivatives by Payment and Performance Risk (Credit Rating) [Axis] Credit Rating [Domain] Investment Grade External Credit Rating, Investment Grade [Member] Credit Derivatives by Underlying Asset Class [Axis] Underlying Asset Class [Domain] Financial institutions [Member] Financial institutions Financial institutions. Energy marketers and traders [Member] Energy marketers and traders Energy marketers and traders. Gas and electric utilities [Member] Gas and electric utilities Gas and electric utilities. Credit Derivatives [Line Items] Gross Credit Exposure From Derivative Contracts [Abstract] Gross credit exposure from derivative contracts The gross credit exposure from derivative contracts. Counterparty [Abstract] Counterparty type Derivative Counterparty. Credit Risk Exposure Before Credit Reserve Credit risk exposure before credit reserve Credit risk exposure before credit reserve Credit risk exposure before credit reserve. Credit Reserves Credit reserves Credit reserves. Credit Exposure After Credit Reserve Credit exposure after credit reserve Credit exposure after credit reserve. Fair Value, Concentration of Risk, Disclosure Items [Axis] Fair Value, Concentration of Risk, Disclosure Items [Domain] Fair Value, Concentration of Credit Risk, Master Netting Arrangements Fair Value, Concentration of Credit Risk, Master Netting Arrangements [Member] Net Credit Exposure From Derivative Contracts [Abstract] Net credit exposure from derivative contracts The net credit exposure from derivative contracts. Financial Instruments Derivatives Guarantees And Concentration Of Credit Risk (Textuals) [Abstract] Financial Instruments Derivatives Guarantees and Concentration of Credit Risk (Textuals) [Abstract] Financial instruments derivatives guarantees and concentration of credit risk. Percentage of long term debt publicly traded Percentage of long term debt publicly traded Percentage of long term debt publicly traded. Cost Investments Not Publicly Traded Cost investments not publicly traded Cost investments not publicly traded. Expected duration of future net cash flows for derivatives classified as current Expected duration of future net cash flows for derivatives classified as current (Months) Expected duration of future net cash flows for derivatives classified as current. Collateral totaling of credit risk Collateral Already Posted, Aggregate Fair Value Aggregate fair value of net derivative liability position Derivative, Net Liability Position, Aggregate Fair Value Reduced liability balance of credit risk Reduced liability balance of credit risk Reduced liability balance of credit risk. Additional collateral of credit risk Additional Collateral, Aggregate Fair Value Maximum period hedged in cash flow hedge (Years) Maximum Length of Time Hedged in Cash Flow Hedge Net gains of cash flow hedge to be reclassified into earnings within next year Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Tax Provision Benefit Of Net Gains Of Cash Flow Hedges To Be Reclassified Into Earnings Within Next Year Tax provision benefit of net gains of cash flow hedges to be reclassified into earnings within next year Tax provision benefit of net gains of cash flow hedges to be reclassified into earnings within next year. Maximum potential exposure of guarantees Guarantor Obligations, Maximum Exposure, Undiscounted Carrying value of guarantees included in accrued liabilities Guarantor Obligations, Current Carrying Value Portion Of Net Credit Exposure From Derivatives Counterparty Associated With Investment Grade Counterparties Portion of net credit exposure from derivatives represented by seven largest net counterparty associated with investment grade counterparties Portion of net credit exposure from derivatives counterparty associated with investment grade counterparties. Portion Of Net Credit Exposure From Derivatives Associated With Exploration And Productions Hedging Facility Portion of net credit exposure from derivatives represented by counterparty positions associated with Exploration & Production's hedging facility PortionOfNetCreditExposureFromDerivativesAssociatedWithExplorationProductionsHedgingFacility Collateral support under Exploration Productions hedging facility Collateral support under Exploration Productions hedging facility Collateral support under Exploration Productions hedging facility. Collateral support related to other derivative positions Collateral support related to other derivative positions Collateral support related to other derivative positions. Contingent Liabilities (Details) [Abstract] Contingent Liabilities. Schedule of Related Party Transactions, by Related Party [Table] Related Party Transactions, by Related Party [Axis] Related Party [Domain] Former Operations [Member] Former Operations Former Operations. Environmental Protection Agency [Member] Environmental Protection Agency Environmental Protection Agency. Natural Gas Under Ground Storage Facilities [Member] Natural gas underground storage facilities Natural gas underground storage facilities. Gas Pipeline [Member] Gas Pipeline Gas Pipeline. Gulf Liquid [Member] Gulf Liquids Gulf Liquid. Pending or Threatened Litigation Pending or Threatened Litigation [Member] Related Party Transaction [Line Items] Contingent Liabilities (Textuals) [Abstract] Contingent Liabilities (Textuals) [Abstract] Contingent Liabilities. Accrued environmental loss liabilities Accrued Environmental Loss Contingencies, Noncurrent Loss Contingency For Actual Damages Estimated exposure for actual damages Loss Contingency For Actual Damages. Loss Contingency Potential Interest Potential interest in addition to actual damages Loss Contingency Potential Interest. Loss Contingency, Range of Possible Loss, Portion Not Accrued Possible ultimate judgement in excess of accrual Loss Contingency Accrual Reduction Gross Loss contingency accrual reduction Loss contingency accrual reduction gross - includes related interest. Loss contingency accrued interest reduction Loss contingency accrued interest reduction Loss contingency accrued interest reduction. Litigation Award Damages Litigation award against Gulf Liquids, Damages Litigation Award Damages. Litigation Award Interest Litigation award against Gulf Liquids, Interest Litigation Award Interest. Loss Contingency Damages Sought Value Assertion of Counterclaim The value (monetary amount) of the award the plaintiff seeks in the legal matter. Contingent Liabilities Additional (Textuals) [Abstract] Contingent Liabilities Additional (Textuals) [Abstract] Contingent Liabilities Additional. Segment Disclosures (Details) [Abstract] Segment Disclosures. Schedule of Segment Reporting Information, by Segment [Table] Segment Reporting, Amount Per Revenue Reconciling Item [Axis] Segment Reporting, Revenue Reconciling Item, Name [Domain] External [Member] External External. Internal [Member] Internal Internal. Segment operating income [Member] Segment operating income Segment operating income. Segment Reporting Information [Line Items] Reconciliation of segment revenues and segment profit (loss) Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Abstract] Segment revenues: Segment Reporting Information, Revenue [Abstract] Segment Profit Loss Segment profit (loss) Segment profit loss Less: Equity earnings (losses) Income (Loss) from Equity Method Investments, Total Less:Equity earnings Income (Loss) from Equity Method Investments Segment Disclosures (Textuals) [Abstract] Segment Disclosures (Textuals) [Abstract] Segment Disclosures. Other General Expense General corporate expenses General corporate expenses Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Text Block] Stock options excluded Gas Management [Member] Gas Management. Gas Management [Member] Segment Reporting, Entity Consolidated Assets [Abstract] Total assets by reporting segment Increase Decrease In Margin Deposits And Customer Margin Deposits Payable Margin deposits and customer margin deposits payable Increase decrease in margin deposits and customer margin deposits payable. Segment Reporting Information, by Segment [Axis] Reporting Segment [Domain] Segment reporting information gain loss from investments Less: Income (loss) from investments Segment reporting information gain loss from investments. Investment [Axis] Investment [Domain] Discontinued Operations (Textuals) [Abstract] Discontinued operations. Discontinued Operations (Textuals) [Abstract] Discontinued Operations Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax Discontinued Operation, Income (Loss) from Discontinued Operation During Phase-out Period, before Income Tax, Total Income (loss) from discontinued operations before impairment and income taxes Discontinued Operation, Provision for Loss (Gain) on Disposal, before Income Tax Impairment Discontinued Operation, Provision for Loss (Gain) on Disposal, before Income Tax, Total Percentage Of Total Assets Attributable To Discontinued Operations Percentage of total assets attributable to discontinued operations Percentage of total assets attributable to discontinued operations. Asset Sales And Other Accruals Disclosures [Text Block] Asset Sales and Other Accruals Asset sales and other accruals disclosures. Project Feasibility Costs Reversed From Expense To Capital Project feasiblity costs reversal Project feasibility costs reversed from expense to capital. Equity Method Investment, Realized Gain (Loss) on Disposal Equity Method Investment, Realized Gain (Loss) on Disposal, Total Payment received from equity method investment sold Gains (Losses) on Extinguishment of Debt Early debt retirement costs Gains (Losses) on Extinguishment of Debt, Total Early debt retirement costs Fair Value Disclosures [Text Block] Fair Value Measurements Assets Fair Value Disclosure [Abstract] Assets: Assets fair value disclosure. Liabilities Fair Value Disclosure [Abstract] Liabilities: Liabilities fair value disclosure. Schedule Of Components Of Income Tax Expense Benefit Table [Text Block] Provision (benefit) for income taxes from continuing operations Schedule of components of income tax expense benefit. Anticipated Cash Payments For Tax Settlements Range Minimum Anticipated cash payments (net of refunds) to taxing authorities, minimum Anticipated cash payments for tax settlements range minimum. Anticipated Cash Payments For Tax Settlements Range Maximum Anticipated cash payments (net of refunds) to taxing authorities, maximum Anticipated cash payments for tax settlements range maximum. Deductions Used In Calculation Of Royalty Payments Deductions used in calculation of royalty payments. Deductions used in calculation of royalty payments. Asset Sales and Other Accruals [Abstract] Asset Sales And Other Accruals Abstract. Contingent Liabilities [Abstract] Contingent Liabilities Abstract. Deferred Income Tax Expense Benefit From Continuing And Discontinued Operations Provision (benefit) for deferred income taxes Deferred Income Tax Expense Benefit From Continuing And Discontinued Operations. Reconciliation of Assets from Segment to Consolidated [Text Block] Total assets by reporting segment Discontinued Operations [Abstract] Discontinued Operations [Abstract].