Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Reconciliation of total cost of share-based awards to the after tax effect on net income Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Performance based units outstanding Performance Based Units Outstanding [Table Text Block] Schedule of equity and liability awards outstanding. Fair Value Disclosures [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Public Utilities, General Disclosures [Abstract] Gas Rate and Regulatory Matters Public Utilities General Disclosures - Gas [Text Block] Public Utilities General Disclosures - Gas [Text Block] Quarterly Financial Information Disclosure [Abstract] Summarized quarterly financial data Quarterly Financial Information [Table Text Block] Debt Disclosure [Abstract] Schedule of Short-term Debt [Table] Schedule of Short-term Debt [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Utility Holdings [Member] Utility Holdings [Member] Refers to an entity under the control of the same parent as another entity (that is, a sister company). Indiana Gas [Member] Indiana Gas [Member] Refers to an entity under the control of the same parent as another entity (that is, a sister company). SIGECO [Member] SIGECO [Member] Refers to an entity under the control of the same parent as another entity (that is, a sister company). Vectren Capital Corp. [Member] Vectren Capital Corp [Member] Refers to an entity under the control of the same parent as another entity (that is, a sister company). Statement, Business Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Mortgages [Member] Mortgages [Member] Bonds subject to mandatory tender in September 2017 [Member] Bonds subject to mandatory tender in September 2017 [Member] Bonds subject to mandatory tender in September 2017 [Member] Bonds subject to mandatory tender in September 2020 [Member] Bonds subject to mandatory tender in September 2020 [Member] Bonds subject to mandatory tender in September 2020 [Member] Nonutility Group [Member] Nonutility Group [Member] Nonutility Group Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Environmental Improvement Revenue Bonds, Warrick County, 2055, 2.375%, Series 2015 [Member] Environmental Improvement Revenue Bonds, Warrick County, 2055, 2.375%, Series 2015 [Member] Environmental Improvement Revenue Bonds, Warrick County, 2055, 2.375%, Series 2015 [Member] Environmental Improvement Revenue Bonds, Mount Vernon, 2055, 2.375%, Series 2015 [Member] Environmental Improvement Revenue Bonds, Mount Vernon, 2055, 2.375%, Series 2015 [Member] Environmental Improvement Revenue Bonds, Mount Vernon, 2055, 2.375%, Series 2015 [Member] Fixed Rate Senior Unsecured Notes [Member] Unsecured Debt [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] 2015, 5.45% [Member] Fixed Rate Senior Unsecured Notes 2015545 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2018, 5.75% [Member] Fixed Rate Senior Unsecured Notes 2018575 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2020, 6.28% [Member] Fixed Rate Senior Unsecured Notes 2020628 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2021, 4.67 [Member] Fixed Rate Senior Unsecured Notes 2021467 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2023, 3.72% [Member] Fixed Rate Senior Unsecured Notes 2023372 [Member] Fixed Rate Senior Unsecured Notes 2023372 [Member] 2026, 5.02% [Member] Fixed Rate Senior Unsecured Notes 2026502 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2028, 3.20% [Member] Fixed Rate Senior Unsecured Notes 2028320 [Member] Fixed Rate Senior Unsecured Notes 2028320 [Member] 2035, 6.10% [Member] Fixed Rate Senior Unsecured Notes 2035610 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2035,3.90% [Member] Fixed Rate Senior Unsecured Notes 2035,3.90% [Member] Fixed Rate Senior Unsecured Notes 2035,3.90% [Member] 2041, 5.99% [Member] Fixed Rate Senior Unsecured Notes 2041599 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2042, 5.00% [Member] Fixed Rate Senior Unsecured Notes 20425 [Member] 2043, 4.25% [Member] FixedRateSeniorGuaranteedNotes2043425 [Member] FixedRateSeniorGuaranteedNotes2043425 [Member] 2045,4.36% [Member] Fixed Rate Senior Unsecured Notes 2045,4.36% [Member] Fixed Rate Senior Unsecured Notes 2045,4.36% [Member] 2055,4.51% [Member] Fixed Rate Senior Unsecured Notes 2055,4.51% [Member] Fixed Rate Senior Unsecured Notes 2055,4.51% [Member] 2015, Series E, 7.15% [Member] Fixed Rate Senior Unsecured Notes 2015 Series E 715 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2015, Series E, 6.69% [Member] Fixed Rate Senior Unsecured Notes 2015 Series E 669 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2015, Series E1, 6.69% [Member] Fixed Rate Senior Unsecured Notes 2015 Series E 1669 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2025, Series E, 6.53% [Member] Fixed Rate Senior Unsecured Notes 2025 Series E 653 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2027, Series E, 6.42% [Member] Fixed Rate Senior Unsecured Notes 2027 Series E 642 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2027, Series E, 6.68% [Member] Fixed Rate Senior Unsecured Notes 2027 Series E 668 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2027, Series F, 6.34% [Member] Fixed Rate Senior Unsecured Notes 2027 Series F 634 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2028, Series F, 6.36% [Member] Fixed Rate Senior Unsecured Notes 2028 Series F 636 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2028, Series F, 6.55% [Member] Fixed Rate Senior Unsecured Notes 2028 Series F 655 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2029, Series G, 7.08% [Member] Fixed Rate Senior Unsecured Notes 2029 Series G 708 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2016, 1986 Series, 8.875% [Member] First Mortgage Bonds20161986 Series8875 [Member] A loan to finance the purchase of utility property where the lender has a lien on the property as collateral for the loan. 2022, 2013 Series C, 1.95% tax exempt [Member] First Mortgage Bonds 20222013 Series C 195 Tax Exempt [Member] First Mortgage Bonds 20222013 Series C 195 Tax Exempt [Member] 2024, 2013 Series D, 1.95% tax exempt [Member] First Mortgage Bonds 20242013 Series D 195 Tax Exempt [Member] First Mortgage Bonds 20242013 Series D 195 Tax Exempt [Member] 2025, 2014 Series B, 1.045% tax exempt [Member] FirstMortgageBonds20252014CurrentAdjustbaleRate1045TaxExempt [Member] FirstMortgageBonds20252014CurrentAdjustbaleRate1045TaxExempt [Member] 2029, 1999 Senior Notes, 6.72% [Member] First Mortgage Bonds 20291999 Senior Notes 672 [Member] A loan to finance the purchase of utility property where the lender has a lien on the property as collateral for the loan. 2037, 2013 Series E 1.95% Tax Exempt [Member] First Mortgage Bonds 20372013 Series E 195 Tax Exempt [Member] First Mortgage Bonds 20372013 Series E 195 Tax Exempt [Member] 2038, 2013 Series A, 4.00% Tax Exempt [Member] First Mortgage Bonds 2038 2013 Series A 400 Tax Exempt [Member] First Mortgage Bonds 2038 2013 Series A 400 Tax Exempt [Member] 2043, 2013 Series B 4.05% Tax Exempt [Member] FirstMortgageBonds20432013SeriesB405TaxExemptMember [Member] First Mortgage Bonds 2043, 2013 Series B 4.05% Tax Exempt [Member] 2044, 2014 Series A 4.00% Tax Exempt [Member] FirstMortgageBonds20442014SeriesA400TaxExempt [Member] [Member] FirstMortgageBonds20442014SeriesA400TaxExempt [Member] 2015, 5.31% [Member] Fixed Rate Senior Unsecured Notes 2015531 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2016, 6.92% [Member] Fixed Rate Senior Unsecured Notes 2016692 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2017, 3.48% [Member] Fixed Rate Senior Unsecured Notes 2017348 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2019, 7.30% [Member] Fixed Rate Senior Unsecured Notes 2019730 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2022, 3.33% [Member] Fixed Rate Senior Unsecured Notes 2022, 3.33% [Member] Fixed Rate Senior Unsecured Notes 2022, 3.33% [Member] 2025, 4.53% [Member] Fixed Rate Senior Unsecured Notes 2025453 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. 2030,3.90% [Member] Fixed Rate Senior Unsecured Notes 2030,3.90% [Member] Fixed Rate Senior Unsecured Notes 2030,3.90% [Member] 2014, 6.37% [Member] Fixed Rate Senior Unsecured Notes 2014637 [Member] A debt obligation not collateralized by pledge, mortgage or other lien in the entity's assets. Debt Instrument [Line Items] Debt Instrument [Line Items] Long term debt [Abstract] Long-term Debt, Unclassified [Abstract] Extinguishment of Debt, Amount Extinguishment of Debt, Amount Debt Issuance Debt Instrument, Face Amount Fixed rate stated percentage (in hundredths) Debt Instrument, Interest Rate, Stated Percentage Total long term debt outstanding Long-term Debt, Gross Current maturities of long-term debt Long-term Debt, Current Maturities Debt Issuance Costs, Net Debt Issuance Costs, Net Unamortized debt premium and discount - net Debt Instrument, Unamortized Discount (Premium), Net Long-term debt - net of current maturities and debt subject to tender Long-term Debt - Net of Current Maturities And Debt Subject to Tender Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any. Also excludes the portion of debt that could be repaid in one year at the option of the holder. Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Maximum Amount Financial Instruments Subject to Mandatory Redemption, Settlement Terms, Maximum Amount Long-term Debt Long-term Debt Short-term borrowings Short-term Debt Future long term debt sinking fund fund requirements and maturities [Abstract] Future long term debt sinking fund requirements and maturities [Abstract] Future long term debt sinking fund requirements and maturities Annual sinking fund requirement fixed percentage (in hundredths) Annual sinking fund requirement fixed percentage (in hundredths) This element represents the percentage used to calculate annual sinking fund requirement. Utility plant remaining unfunded under mortgage indenture Utility Plant Remaining Unfunded Under Sigecos Mortgage Indenture This element represents the portion of the utility plant remaining unfunded as of the balance sheet date under the mortgage indenture. Gross utility plant balance subject to the mortgage indenture Sigecos Gross Utility Plant Balance Subject To Mortgage Indenture This element represents the gross utility plant balance subject to the mortgage indenture. Maturities of long term debt [Abstract] Maturities of Long-term Debt [Abstract] Debt maturing within 12 months following date of latest balance sheet Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months Debt maturing within two years following date of latest balance sheet Long-term Debt, Maturities, Repayments of Principal in Year Two Debt maturing within three years following date of latest balance sheet Long-term Debt, Maturities, Repayments of Principal in Year Three Debt maturing within four years following date of latest balance sheet Long-term Debt, Maturities, Repayments of Principal in Year Four Debt maturing within five years following date of latest balance sheet Long-term Debt, Maturities, Repayments of Principal in Year Five Debt maturing thereafter 5 years following date of the latest balance sheet Long-term Debt, Maturities, Repayments of Principal after Year Five Covenants [Abstract] Covenants [Abstract] Debt to consolidated total capitalization - maximum ratio Debt to consolidated total capitalization - maximum ratio Debt to consolidated total capitalization - maximum ratio Statement of Financial Position [Abstract] Statement [Table] Statement [Table] Statement, Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Statement [Line Items] Statement [Line Items] ASSETS Assets [Abstract] Current Assets Assets, Current [Abstract] Reserves Allowance for Doubtful Accounts Receivable, Current LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity [Abstract] Common Shareholders' Equity Stockholders' Equity Attributable to Parent [Abstract] Common stock Shares, Issued (in shares) Common Stock, Shares, Issued Common stock, Shares Outstanding (in shares) Common Stock, Shares, Outstanding Equity Method Investments and Joint Ventures [Abstract] Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] Schedule of Equity Method Investment, Equity Method Investee, Name [Axis] Investment, Name [Axis] Equity Method Investee, Name [Domain] Investment, Name [Domain] ProLiance Holdings, LLC [Member] Proliance Holdings Llc [Member] Information related to the legal entity ProLianceHoldings, LLC. LA Storage [Member] LA Storage [Member] LA Storage [Member] Affiliated Entity [Member] Affiliated Entity [Member] Corporate Joint Venture [Member] Corporate Joint Venture [Member] Equity Method Investment, Ownership Percentage Equity Method Investment, Ownership Percentage Combined Joint Venture Ownership Percentage Combined Joint Venture Ownership Percentage Equity method investment, combined joint venture ownership percentage Equity Method Investment, Voting and Governance Rights Equity Method Investment, Voting and Governance Rights Equity method investment, voting and governance rights Equity Method Investments Equity Method Investments Summarized balance sheet information [Abstract] Equity Method Investment, Summarized Financial Information [Abstract] Equity method investment, summarized financial information, cash Equity method investment, Summarized Financial Information, Cash The amount of cash reported by an equity method investment of the entity. Equity method investment,summarized financial information, storage assets Equity Method investment,Summarized Financial Information, Storage Assets The amount of the storage assets reported by an equity method investment of the entity. Equity method investment, summarized financial information, other asset investment Equity Method investment, Summarized Financial Information, Other Asset Investment The amount of other asset investments reported by an equity method investment of the entity. Equity method investment, gross investment in equity method investee Equity method investment, gross investment in equity method investee Equity method investment, gross investment in equity method investee Investments in unconsolidated affiliates Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures Other nonutility investments Other nonutility investments Other long-term nonutility investments not classified elsewhere in the taxonomy. Share-Based Compensation and Deferred Compensation Arrangements Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Goodwill and Intangible Assets Disclosure [Abstract] Intangible Assets Schedule of Intangible Assets, Excluding Goodwill, By Major Class [Table Text Block] Tabular disclosure of the carrying value of intangible assets, excluding goodwill, in total and by major class. A major class is composed of intangible assets that can be grouped together because they are similar, either by their nature or by their use in the operations of the company. Valuation and Qualifying Accounts [Abstract] Valuation and Qualifying Accounts Disclosure [Table] Valuation and Qualifying Accounts Disclosure [Table] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves Type [Axis] Valuation Allowances and Reserves [Domain] Valuation Allowances and Reserves [Domain] Accumulated Provision for Uncollectible Accounts [Member] Allowance for Doubtful Accounts [Member] Reserve for Impaired Notes Receivable [Member] Allowance for Loans and Leases Receivable [Member] Business Restructuring Reserves [Member] Business Restructuring Reserves [Member] Valuation and Qualifying Accounts Disclosure [Line Items] Valuation and Qualifying Accounts Disclosure [Line Items] Balance, at beginning of year Valuation Allowances and Reserves, Balance Additions charged to expenses Valuation Allowances and Reserves, Additions for Charges to Cost and Expense Additions charged to other accounts Valuation Allowances and Reserves, Additions for Charges to Other Accounts Deductions from Reserves, Net Valuation Allowances and Reserves, Deductions Balance, at end of period Income Tax Disclosure [Abstract] Reconciliation of the federal statutory rate to the effective income tax rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Significant components of the net deferred tax liability (assets) Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Components of income tax expense and utilization of investment tax credits Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Additional Balance Sheet and Operational Information [Abstract] Additional Balance Sheet and Operational Information Additional Balance Sheet And Operational Information [Text Block] Disclosure related to additional balance sheet and operational information, including inventories, prepayments and other current assets, investments in unconsolidated affiliates, other utility and corporate investments, goodwill, accrued liabilities, asset retirement obligations, equity in earnings (losses) of unconsolidated affiliates, other income - net, and supplemental cash flow information. Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income Accumulated Other Comprehensive Income Note Disclosure [Text Block] The entire disclosure for accumulated other comprehensive income. Public Utilities General Disclosures [Table] Public Utilities General Disclosures [Table] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] INDIANA INDIANA OHIO OHIO Public Utilities, Regulatory Proceeding [Axis] Public Utilities, Regulatory Proceeding [Axis] Public Utilities, Regulatory Proceeding [Domain] Public Utilities, Regulatory Proceeding [Domain] Indiana Recovery and Deferral Mechanisms [Member] Indiana Recovery and Deferral Mechanisms [Member] Indiana Recovery and Deferral Mechanisms [Member] Senate Bill 251 and 560 [Member] Senate Bill 251 and 560 [Member] Senate Bill 251 and 560 [Member] Ohio Recovery and Deferral Mechanisms [Member] Ohio Recovery and Deferral Mechanisms [Member] Ohio Recovery and Deferral Mechanisms [Member] Ohio House Bill95 [Member] Ohio House Bill95 [Member] Information on the Ohio House Bill 95. Range [Axis] Range [Axis] Range [Domain] Range [Domain] Maximum [Member] Maximum [Member] Minimum [Member] Minimum [Member] Public Utilities, General Disclosures [Line Items] Public Utilities, General Disclosures [Line Items] Allowable capital expenditures under Vectren programs Allowable capital expenditures under Vectren programs Annual Capital Expenditures under the Vectren bare steel and cast iron main replacement program allowed to receive preferred accounting treatment (deferred depreciation and continuation of AFUDC after the in-service date). Limitations of deferrals of debt-related post in service carrying costs Limitations of deferrals of debt-related post in service carrying costs Limitations of deferrals of debt-related post in service carrying costs Regulatory assets Regulatory Assets, Noncurrent Length of project plan required for recovery under new legislation Length of project plan required for recovery under new legislation Length of project plan required for recovery under new legislation Percentage of costs eligible for recovery using periodic rate recovery mechanism Percentage of costs eligible for recovery using periodic rate recovery mechanism Percentage of costs eligible for recovery using periodic rate recovery mechanism Percentage of project costs to be deferred for future recovery Percentage of project costs to be deferred for future recovery Percentage of project costs to be deferred for future recovery Amount of projects not approved for recovery Amount of projects not approved for recovery Amount of projects not approved for recovery Amount of single project excluded from recovery Amount of single project excluded from recovery Of the amount of projects not approved, amount represents one single project within the total amount not approved. Payments for capital improvements Payments for Capital Improvements Capital Expenditure Increases Capital Expenditure Increases Amount of capital expenditure increases included in update to seven-year plan. Total Capital Expenditures Under Seven Year Plan Total Capital Expenditures Under Seven Year Plan Total Capital Expenditures Under Seven Year Plan Amount of Capital Investment Expected Over Next Five Years Recoverable Under DRR Amount of Capital Investment Expected Over Next Five Years Recoverable Under DRR The capital investment expected over the next 5 years that will be recoverable under VEDO’s DRR mechanism. Bill impact per customer per month Bill impact per customer per month The limit on the deferrals, represented as a bill impact per customer per month, allowed under VEDO's Capital Expenditure Program filed under Ohio House Bill 95. Statement of Comprehensive Income [Abstract] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Pensions and Other Benefits [Member] Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Net Income Net Income (Loss) Attributable to Parent Amounts arising during the year before tax Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Tax Reclassifications to periodic cost before tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Pension and Other Postretirement Benefit Plans, for Net Gain (Loss), before Tax Deferrals to regulatory assets Other Comprehensive Income Deferrals To Regulatory Assets Before Tax Portion of other comprehensive income deferrals to regulatory assets associated with pension and other postretirment benefit plans, before tax. Income taxes Other Comprehensive Income (Loss), Tax Other comprehensive income Other Comprehensive Income (Loss), Net of Tax TOTAL COMPREHENSIVE INCOME Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Segment Reporting [Abstract] Segment Reporting Segment Reporting Disclosure [Text Block] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Discontinued Operations and Disposal Groups [Abstract] Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] Utility Group [Member] Utility Group [Member] Short-term Debt [Line Items] Short-term Debt [Line Items] Short-term borrowings [Abstract] Short-term Debt [Abstract] Short-term borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Short term borrowings available Line of Credit Facility, Remaining Borrowing Capacity Balance Outstanding, end of period Weighted Average Interest Rate, end of period (in hundredths) Short-term Debt, Weighted Average Interest Rate Balance Outstanding, annual average Short-term Debt, Average Outstanding Amount Weighted Average Interest Rate, annual average (in hundredths) Weighted Average Interest Rate, annual average This element reflects the calculation of the average interest rate weighted by the amount of debt outstanding by type or by instrument during the period under review. Maximum Month End Balance Outstanding Short-term Debt, Maximum Month-end Outstanding Amount Income Statement [Abstract] OPERATING REVENUES Revenue, Net [Abstract] Gas utility Regulated Operating Revenue, Gas Electric utility Electric Domestic Regulated Revenue Nonutility Other Revenue, Net Total operating revenues Revenue, Net OPERATING EXPENSES Operating Expenses [Abstract] Cost of gas sold Cost of Natural Gas Purchases Cost of fuel and purchased power Cost of Domestic Regulated Electric Cost of nonutility revenues Other Cost of Operating Revenue Other operating Other Cost and Expense, Operating Depreciation and amortization Depreciation, Depletion and Amortization Taxes other than income taxes Taxes other than income taxes All taxes not related to income of the entity. Total operating expenses Operating Expenses OPERATING INCOME Operating Income (Loss) OTHER INCOME (EXPENSE) Nonoperating Income (Expense) [Abstract] Equity in earnings (losses) of unconsolidated affiliates Income (Loss) from Equity Method Investments Other income - net Other Nonoperating Income (Expense) Total other income Nonoperating Income (Expense) Interest expense Interest Expense INCOME BEFORE INCOME TAXES Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income taxes Income Tax Expense (Benefit) Net income AVERAGE COMMON SHARES OUTSTANDING (in shares) Weighted Average Number of Shares Outstanding, Basic DILUTED COMMON SHARES OUTSTANDING (in shares) Weighted Average Number of Shares Outstanding, Diluted EARNINGS PER SHARE OF COMMON STOCK: Earnings Per Share [Abstract] BASIC (in dollars per share) Earnings Per Share, Basic Intangible Assets Intangible Assets Disclosure [Text Block] Total cost of share-based compensation Share-based Compensation Less capitalized cost Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized Amount Total in other operating expense Allocated Share-based Compensation Expense Less income tax benefit in earnings Employee Service Share-based Compensation, Tax Benefit from Compensation Expense After tax effect of share-based compensation Allocated Share-based Compensation Expense, Net of Tax Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangement by Share-based Payment Award, Award Type and Plan Name [Axis] Award Type [Axis] Share-based Compensation Arrangements by Share-based Payment Award, Award Type and Plan Name [Domain] Equity Award [Domain] Performance Based Units Equity Method [Member] Performance Based Units Equity Method [Member] Incremental common shares attributable to performance based units accounted for on the equity method of accounting that were not included in diluted earnings per share (EPS) because to do so would increase EPS amounts or decrease loss per share amounts for the period presented. Performance based units are awards for which sale is contractually or governmentally restricted for a given period of time. Performance Based Units Liability Method [Member] Performance Based Units Liability Method [Member] Performance Based Units Liability Method [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Vesting period for performance-based awards to executives and key non-officer employees (in years) Vesting period for performance-based awards to executives and key non-officer employees Description of the period of time over which an employee's right to the share based award is no longer contingent on satisfaction of either a service condition, market condition, and/or performance condition. Vesting period for time-vested awards to non-officer employees (in years) Vesting Period For Time Vested Awards To Non Officer Employees Description of the period of time over which an employee's right to a share based award ratably vests at annual intervals. Employees must be employed at date of lift. Vesting period for awards to certain non-utility employees (in years) Vesting period for awards to certain non-utility employees (in years) Vesting period for awards to certain non-utility employees (in years) Vesting period for awards to non-employee directors (in years) Vesting period for awards to non-employee directors Description of the period of time over which a non-employee director's right to a share based award is fully vested. Non-employee director must be an active director at the date of lift. Performance Measurement Time Frame For Grants To Executives And Key Nonofficer Emplyees In Years Performance Measurement Time Frame For Grants To Executives And Key Nonofficer Emplyees In Years Upper range of share based awards that may potentially be taken in cash (in units) Upper range of share based awards that may potentially be taken in cash Upper range of share based awards that may potentially be taken in cash due to ability to participate in the Company's deferred compensation plan. Total unrecognized compensation cost related to performance based awards Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Weighted-average life of unrecognized compensation cost (in years) Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Total fair value of liability awards vested Share Based Compensation Arrangement By Share Based Payment Award Liability Awards Vested In Period Total Fair Value The total fair value of liability awards for which the grantee gained the right during the reporting period, by satisfying performance, and/or service requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. Total fair value of equity awards vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Share Based Payment Award Equity Instruments Other Than Options [Roll Forward] Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Performance based awards at beginning of period (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Performance based awards at end of period (in shares) Weighted average grant date fair value at beginning of period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Weighted average grant date fair value of shares granted during period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted average grant date fair value of shares vested during period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Weighted average grant date fair value of shares forfeited during period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Weighted average grant date fair value at end of period (in dollars per share) Deferred Compensation Plans [Abstract] Deferred Compensation Arrangements [Abstract] Liability associated with deferred compensation plans Deferred Compensation Liability, Current and Noncurrent Portion of liability classified in Accrued liabilities Deferred Compensation Liability, Current Impact of deferred compensation plans on Other operating expenses Deferred Compensation Plan (Income) Expense in Other Operating Expenses This amount represents the impact of gains and losses, as well as savings and match amounts and pass through dividends that were recognized in the income statement. Amount recorded in earnings related to the investment activities in phantom stock associated with deferred compensation plans (Income) Expense Impact Of Phantom Stock Activites Associated With Deferred Comp Plans This amount represents the portion of gain or loss recognized in the income statement specifically related to Vectren phantom stock in the deferred compensation plans. Cash surrender value of life insurance policies Cash Surrender Value of Life Insurance Earnings (loss) from investments in corporate-owned life insurance policies Life Insurance, Corporate or Bank Owned, Change in Value Regulatory Assets and Liabilities Disclosure [Abstract] Schedule of Regulatory Assets Schedule of Regulatory Assets [Table Text Block] Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Federal Business Unit [Member] Federal Business Unit [Member] Federal Business Unit [Member] Business Acquisition [Line Items] Business Acquisition [Line Items] Effective Date of Acquisition Business Acquisition, Effective Date of Acquisition Business Combination, Liabilities Arising from Contingencies, Amount Recognized Business Combination, Liabilities Arising from Contingencies, Amount Recognized Total Purchase Consideration Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Transaction Costs Business Acquisition, Transaction Costs Amount of Transaction Costs in Other Cost and Expense, Operating Pro Forma Revenue Business Acquisition, Pro Forma Revenue Nonutility Real Estate Other Legacy Holdings [Abstract] Nonutility Real Estate and Other Legacy Holdings Nonutility Real Estate Other Legacy Holdings [Text Block] The entire disclosure of the investments included in the Nonutility business segment. Compensation and Retirement Disclosure [Abstract] Retirement Plans and Other Postretirement Benefits Pension and Other Postretirement Benefits Disclosure [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Customer [Axis] Customer [Axis] Customer [Domain] Customer [Domain] Natural Gas Customers [Member] Natural Gas Customers [Member] Natural Gas Customers [Member] Electric Customers [Member] Electric Customers [Member] Electric Customers [Member] Vectren Energy Delivery of Ohio [Member] Vectren Energy Delivery of Ohio [Member] Vectren Energy Delivery of Ohio [Member] Number of public utility subsidiaries owned by wholly owned subsidiary, Vectren Utility Holdings, Inc. (in number of subsidiaries) Number Of Public Utility Subsidiaries Owned By Wholly Owned Subsidiary Of Company Pertains to the number of public utility subsidiaries owned by wholly owned subsidiary, Vectren Utility Holdings, Inc. Approximate number of customers (in number of customers) Approximate Number Of Customers Pertains to the approximate number customers serviced by the Company. Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Accounts receivable - less reserves of $6.0 & $5.6, respectively Accounts Receivable, Net, Current Accrued unbilled revenues Accrued unbilled revenues Unbilled amounts due for services rendered or products shipped. Also includes cost of uncompleted contracts in excess of related billings, or unbilled accounts receivable, which is expected to be collected withon one year (or one operating cycle, if longer) from the date of the balance sheet. Inventories Inventory, Net Recoverable fuel and natural gas costs Deferred Fuel Cost Prepayments and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Utility Plant Property, Plant and Equipment [Abstract] Original cost Public Utilities, Property, Plant and Equipment, Other Property, Plant and Equipment Less: accumulated depreciation and amortization Public Utilities, Property, Plant and Equipment, Accumulated Depreciation Net utility plant Public Utilities, Property, Plant and Equipment, Net Other utility and corporate investments Other Long-term Investments Nonutility plant - net Property, Plant and Equipment, Net Goodwill Goodwill Other assets Other Assets, Noncurrent TOTAL ASSETS Assets Current Liabilities Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Refundable fuel and natural gas costs Refundable fuel and natural gas costs Electric and gas costs of a regulated entity that are refundable through future rate adjustments. Such costs are a form of regulatory liabilities and are expected to be refunded in less than 1 year through rate adjustments. Accrued liabilities Accrued Liabilities, Current Current maturities of long-term debt Total current liabilities Liabilities, Current Long-term Debt - Net of Current Maturities Long-term Debt, Excluding Current Maturities Deferred Income Taxes and Other Liabilities Liabilities, Noncurrent [Abstract] Deferred income taxes Deferred Tax Liabilities, Net, Noncurrent Regulatory liabilities Regulatory Liability, Noncurrent Deferred credits and other liabilities Deferred Credits and Other Liabilities Total deferred credits and other liabilities Liabilities, Noncurrent Commitments & Contingencies (Notes 7, 17-20) Commitments and Contingencies Common stock (no par value) - issued & outstanding 82.9 & 82.8 shares, respectively Common Stock, Value, Issued Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive income/(loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Total common shareholders' equity Stockholders' Equity Attributable to Parent TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities and Equity Entities [Table] Entity Information [Line Items] Entity Information [Line Items] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Voluntary Filers Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Entity Public Float Entity Public Float Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Document Type Document Type Amendment Flag Amendment Flag Document Period End Date Document Period End Date Current Fiscal Year End Date Current Fiscal Year End Date Accounting Policies [Abstract] Excise taxes and a portion of utility receipts taxes Excise and Sales Taxes Number of operating segments in Utility group Number of operating segments in Utility group The number of operating segments in the Utility group for which income is reviewed to make operating decisions. Number of operating segments in Nonutility group Number of operating segments in the Nonutility Group The number of operating segments in the Nonutility group for which income is reviewed to make operating decisions. Basic and dilutive earnings per share calculation Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Summarized Financial Information of Equity Investment [Table Text Block] Summarized Financial Information of Equity Investment [Table Text Block] Tabular disclosure of financial information of ProLiance Holdings, LLC. Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Investments by type [Abstract] Financial Instruments, Financial Assets, Balance Sheet Groupings [Abstract] Held-to-maturity Securities Held-to-maturity Securities SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS AND RESERVES Schedule of Valuation and Qualifying Accounts Disclosure [Text Block] Environmental Matters Disclosure [Abstract] Site Contingency [Table] Site Contingency [Table] Environmental Remediation Site [Axis] Environmental Remediation Site [Axis] Environmental Remediation by Entity [Domain] Environmental Remediation Site [Domain] Environmental Remediation Contingency [Axis] Environmental Remediation Contingency [Axis] Environmental Remediation Contingency [Domain] Environmental Remediation Contingency [Domain] Ash Ponds [Member] Ash Ponds [Member] Ash Ponds [Member] Site Contingency [Line Items] Site Contingency [Line Items] Amount approved for capital investments on coal-fired generation units Amount approved for capital investments on coal-fired generation units Amount approved for capital investments on coal-fired generation units to comply with new EPA mandates related to mercury and air toxin standards. Amount of capital investments to date in equipment for mercury control Amount of capital investments to date in equipment for mercury control Amount of capital investments to date in equipment for coal fired generation units to control mercury emissions in air and water. Air Quality [Abstract] Air Quality [Abstract] -- None. No documentation exists for this element. -- Percentage of coal fired generating fleet currently being scrubbed for SO2 (in hundredths) Percentage Of Coal Fired Generating Fleet Scrubbed For So2 Percent of coal fired generating fleet currently being scrubbed for SO2. Percentage of coal fired generating fleet currently controlled for NOx (in hundredths) Percentage Of Coal Fired Generating Fleet Controlled For N Ox Percent of coal fired generating fleet currently controlled for Nox. Coal Ash Waste Disposal, Ash Ponds and Water [Abstract] Coal Ash Waste Disposal, Ash Ponds and Water [Abstract] Asset Retirement Obligation Asset Retirement Obligation Estimated spend for ash pond dam reinforcement and other operational changes Estimated spend for ash pond dam reinforcement and other operational changes Estimated spend for ash pond dam reinforcement and other operational changes Estimated capital expenditures to comply with Clean Water Act Estimated capital expenditures to comply with Clean Water Act Estimated capital expenditures related to Clean Water Act granted that new infrastructure is required. Ash Pond and Coal Ash Disposal Exit Costs Initial Anticipated Cost Ash Pond and Coal Ash Disposal Exit Costs Initial Anticipated Cost Initial anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property. Ash Pond and Coal Ash Disposal Exit Costs Revised Anticipated Cost Ash Pond and Coal Ash Disposal Exit Costs Revised Anticipated Cost Revised anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property. Climate Changes [Abstract] Climate Changes [Abstract] Vectren's share of Indiana's CO2 emissions in 2013 (as a percent) Vectren's share of Indiana's total CO2 emissions in 2013 (as a percent) Vectren's share of Indiana's total CO2 emissions in 2013 (as a percent) Percent reduction of Vectren's CO2 emissions since 2005 Percent reduction of Vectren's CO2 emissions since 2005 Percent reduction of Vectren's CO2 emissions since 2005 Long term contract for purchase of electric power generated by wind energy (in megawatts) Long Term Contract For Purchase Electric Power Generated From Wind Energy Long-term contract to purchase stated megawatt of electric power generated by wind energy. Percentage of total electricity obtained by the supplier to meet the energy needs of its retail customers provided by clean energy sources (in hundredths) Percentage Of Total Electricity Obtained By Supplier To Meet Energy Needs Of Its Retail Customers Provided By Clean Energy Sources In Hundredths Percentage of total electricity obtained by the supplier to meet the energy needs of its retail customers provided by clean energy sources (in hundredths). Vectren's emission rate (as measured in lbs CO2/MWh) prior to installation of new technology Vectren's emission rate (as measured in lbs CO2/MWh) prior to installation of new technology Vectren's emission rate (as measured in lbs CO2/MWh) prior to installation of new technology Vectren's emission rate (as measured in lbs CO2/MWh) after installation of new technology Vectren's emission rate (as measured in lbs CO2/MWh) after installation of new technology Vectren's emission rate (as measured in lbs CO2/MWh) after installation of new technology Percentage reduction of lbs CO2/MWh since 2005 Percentage reduction of lbs CO2/MWh since 2005 Percentage reduction of lbs CO2/MWh since 2005 Manufactured Gas Plants Environmental Remediation Obligations [Abstract] Number of sites identified with potential remedial responsibility for entity (in number of sites) Environmental Remediation Number Of Sites With Potential Remedial Responsibility Number of sites identified where the entity may potentially have some remedial responsibility Environmental Remediation Expense Environmental Remediation Expense Insurance Recoveries Insurance Recoveries Total estimated insurance recoveries Total Estimated Insurance Recoveries Total amount expected to be recovered under the terms of the insurance contracts. Accrual for Environmental Loss Contingencies Included In Other Liabilities Accrual for Environmental Loss Contingencies Environmental Matters Environmental Loss Contingency Disclosure [Text Block] Investments in unconsolidated Affiliates [Table] Investments in and Advances to Affiliates [Table] Products and Services [Axis] Products and Services [Axis] Products and Services [Domain] Products and Services [Domain] Gas Utility Services [Member] Gas Utility Services [Member] Infrastructure Services [Member] Infrastructure Services [Member] Infrastructure Services Energy Services [Member] Energy Services [Member] Investments in and Advances to Affiliates Categorization [Axis] Investments in and Advances to Affiliates Categorization [Axis] Investments in and Advances to Affiliates Categorization [Domain] Investments in and Advances to Affiliates Categorization [Domain] Other Nonutility Partnerships and Corporations [Member] Other Nonutility Partnerships and Corporations [Member] Information on equity investments in non-utility partnerships and corporations. Other Utility Investments [Member] Other Utility Investments [Member] Information on other utility equity investments. Other Unconsolidated Affiliates [Member] Other Unconsolidated Affiliates [Member] Information on other unconsolidated affiliates not individually identified. Investments in unconsolidated Affiliates [Line Items] Investments in and Advances to Affiliates [Line Items] Inventory, Net [Abstract] Inventory, Net [Abstract] Gas in storage - at LIFO cost Gas in storage - at LIFO cost The amount of gas in storage, at the balance sheet date, valued using the LIFO (last in, first out) cost method. Coal and Oil for electric generation - at average cost Coal and Oil for electric generation - at average cost The amount of coal and oil for electric generation recorded using the average cost method of costing for inventory present at the reporting date. Materials and supplies Inventory, Raw Materials and Supplies, Gross Other Other Inventory, Gross Total inventories Amount by which cost of replacing inventories carried at LIFO cost exceeded carrying value Excess of Replacement or Current Costs over Stated LIFO Value Prepayments and other current assets [Abstract] Prepaid Expense and Other Assets, Current [Abstract] Prepaid gas delivery service Prepaid gas delivery service Carrying amount as of the balance sheet date of capitalized payments for gas delivery service which will be transported within one year or the normal operating cycle, if longer. Prepaid taxes Prepaid Taxes Other prepayments and current assets Other Assets, Current Total prepayments and other current assets Investments in unconsolidated affiliates [Abstract] Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures [Abstract] Total investments in unconsolidated affiliates Equity in earnings (loss) of unconsolidated affiliates [Abstract] Equity Method Investment, Financial Statement, Reported Amounts [Abstract] Other utility and corporate investments [Abstract] Other Utility And Corporate Investments [Abstract] Cash surrender value of life insurance policies Restricted cash & other investments Other Investments Other utility and corporate investments Other utility and corporate investments Other long-term utility and corporate investments not classified elsewhere in the taxonomy. Accrued liabilities [Abstract] Accrued Liabilities, Current [Abstract] Refunds to customers and customer deposits Customer Refund Liability, Current Accrued taxes Taxes Payable, Current Accrued interest Interest Payable, Current Deferred compensation & post-retirement benefits Pension and Other Postretirement and Postemployment Benefit Plans, Liabilities, Current Accrued salaries and other Accrued Salaries, Current Total accrued liabilities Asset Retirement Obligation [Roll Forward] Asset Retirement Obligation, Roll Forward Analysis [Roll Forward] Asset retirement obligation, beginning balance Accretion Asset Retirement Obligation, Accretion Expense Asset Retirement Obligation, Liabilities Incurred Asset Retirement Obligation, Liabilities Incurred Changes in estimates, net of cash payments Asset Retirement Obligation, Period Increase (Decrease) Asset retirement obligation, ending balance Other - income (expense) - net [Abstract] Other Nonoperating Income (Expense) [Abstract] AFUDC - borrowed funds Public Utilities Allowance For Funds Used During Construction Capitalized Interest Including Certain Post In Service Activities The component of the allowance for funds used during construction during the period comprised of interest on borrowed funds used in financing the construction of regulated assets, which may be reflected as a reduction of interest expense. Also includes capitalized interest for certain post-in-service activities, namely bare steel/cast iron replacement program, where AFUDC continues to accrue after in-service and until recovered through rates. AFUDC - equity funds Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity Interest Costs Capitalized Adjustment Interest Costs Capitalized Adjustment Interest income, net Interest Income (Expense), Net Other nonutility investment impairment charges Other Asset Impairment Charges All other income Other Non-operating Income (Expense), Net Other Non-operating Income (Expense), Net Other income (expense) - net Supplemental cash flow information [Abstract] Supplemental Cash Flow Information [Abstract] Cash paid (received) for [Abstract] Cash paid for [Abstract] Interest Interest Paid Income taxes Income Taxes Paid, Net Accruals related to utility and nonutility plant purchases [Abstract] Noncash Investing and Financing Items [Abstract] Accruals related to utility and nonutility plant purchases Capital Expenditures Incurred but Not yet Paid Regulatory Assets and Liabilities Schedule of Regulatory Assets and Liabilities [Text Block] Organization and Nature of Operations Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Components and changes in accumulated other comprehensive income Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Principles of Consolidation Consolidation, Subsidiaries or Other Investments, Consolidated Entities, Policy [Policy Text Block] Subsequent Events Review Subsequent Events, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Allowance for Uncollectible Accounts Receivables, Policy [Policy Text Block] Inventories Inventory, Policy [Policy Text Block] Property, Plant and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Investments in Unconsolidated Affiliates Equity Method Investments, Policy [Policy Text Block] Goodwill Goodwill and Intangible Assets, Goodwill, Policy [Policy Text Block] Regulation Public Utilities, Policy [Policy Text Block] Postretirement Obligations and Costs Postemployment Benefit Plans, Policy [Policy Text Block] Asset Retirement Obligations Asset Retirement Obligations, Policy [Policy Text Block] Product Warranties, Performance Guarantees and Other Guarantees Guarantees, Indemnifications and Warranties Policies [Policy Text Block] Energy Contracts and Derivatives Derivatives, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy Text Block] Revenues Revenue Recognition, Policy [Policy Text Block] MISO Transactions Miso Transactions Policy [Policy Text Block] With the IURC's approval, the Company is a member of the MISO, a FERC approved regional transmission organization. The MISO serves the electrical transmission needs of much of the Midwest and maintains operational control over the Company's electric transmission facilities as well as that of other Midwest utilities. MISO-related purchase and sale transactions are accounted for on a net hourly position. Net Purchases are recorded in Cost of Fuel and Purchased Power, and net sales are recorded in Electric Utility Revenues. Any revenues received from MISO for transactions not specifically assigned to a unit of power, such as use of the transmission system or other administrative amounts, are reflected in Electric Utility revenues. Any expenses incurred within the MISO market by the Company that are not specifically identified with a unit of power purchased, such as socialized administrative costs, are treated as Other Operating expense. Share-Based Compensation Compensation Related Costs, Policy [Policy Text Block] Excise and Utility Receipts Taxes Revenue Recognition Excise And Sales Taxes Disclosure [Policy Text Block] Describes the policy for accounting for excise and sales tax, i. e. whether the entity presents excise and sales taxes on a gross basis (included in revenues and costs) or a net basis (excluded from revenue). Operating Segments Segment Reporting, Policy [Policy Text Block] Fair Value Measurements Fair Value of Financial Instruments, Policy [Policy Text Block] Reconciliation of the federal statutory rate to the effective income tax rate [Abstract] Effective Income Tax Rate Reconciliation, Percent [Abstract] Statutory rate: (in hundredths) Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent State and local taxes-net of federal benefit (in hundredths) Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Amortization of investment tax credit (in hundredths) Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Percent Depletion (in hundredths) Effective Income Tax Rate Reconciliation, Nondeductible Expense, Depletion, Percent Domestic production deduction (in hundredths) Effective Income Tax Rate Reconciliation, Deduction, Qualified Production Activity, Percent Energy efficiency building deductions (in hundredths) Effective Income Tax Rate Reconciliation, Section 179(d) Effective Income Tax Rate Reconciliation, Section 179(d) energy tax credits Research and development credit (in hundredths) Effective Income Tax Rate Reconciliation, Nondeductible Expense, Research and Development, Percent Other tax credits (in hundredths) Effective Income Tax Rate Reconciliation, Tax Credit, Other, Percent All other-net (in hundredths) Effective Income Tax Rate Reconciliation, Tax Contingency, Other, Percent Effective tax rate (in hundredths) Effective Income Tax Rate Reconciliation, Percent Noncurrent deferred tax liabilities (assets) [Abstract] Components of Deferred Tax Assets and Liabilities [Abstract] Depreciation and cost recovery timing differences Deferred Tax Liabilities, Property, Plant and Equipment Regulatory assets recoverable through future rates Deferred Tax Liabilities, Regulatory Assets and Liabilities Alternative minimum tax carryforward Alternative Minimum Tax Carryforward Long Term The cumulative amount of future tax effects arising from the unused tax credit carryforward that cannot be utilized on the tax return during a year that may be carried forward to reduce taxable income or taxes payable in a future year; a tax credit carryforward is the amount by which tax credits available for utilization exceed statutory limitations. Employee benefit obligations Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits Net operating loss and other carryforwards Deferred Tax Assets Operating Loss Carryforwards And General Business CreditsNoncurrent The sum of the tax effects as of the balance sheet date of the noncurrent portion of the amount of excesses of tax deductions over gross income in a year which cannot be used on the tax returns in the current year but can be carried forward to reduce taxable income or income taxes payable in a future year, for which there must be sufficient tax-basis income to utilize a portion or all of the carryforward amount to realize the deferred tax asset. Also includes general business credits. Regulatory liabilities to be settled through future rates Deferred Tax Assets, Regulatory Assets and Liabilities Impairments Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Impairment Losses Deferred fuel costs-net Deferred Tax Liability Fuel Costs, Net The cumulative amount of the estimated future tax effects attributable to other temporary differences not otherwise specified in this taxonomy that were expensed for tax purposes but capitalized in conformity with generally accepted accounting principles, or which were recognized as revenue under GAAP but not for tax purposes, which will reverse in future periods. Other - net Deferred Tax Liabilities, Other Net noncurrent deferred tax liability Net noncurrent deferred tax liability Represents the noncurrent portion of deferred tax liabilities, which result from applying the applicable tax rate to net taxable temporary differences pertaining to each jurisdiction to which the entity is obligated to pay income tax. A noncurrent taxable temporary difference is a difference between the tax basis and the carrying amount of a noncurrent asset or liability in the financial statements prepared in accordance with generally accepted accounting principles. In a classified statement of financial position, an enterprise separates deferred tax liabilities and assets into a current amount and a noncurrent amount. Deferred tax liabilities and assets are classified as current or noncurrent based on the classification of the related asset or liability for financial reporting. A deferred tax liability or asset that is not related to an asset or liability for financial reporting, including deferred tax assets related to carryforwards, are classified according to the expected reversal date of the temporary difference. Investment tax credits Investment Tax Credit Remaining life of NOL's and business credit carryforwards (in years) Operating Loss Carryforwards, Limitations on Use Operating Loss Carryforwards, Valuation Allowance Operating Loss Carryforwards, Valuation Allowance Components of income tax expense and utilization of investment tax credits [Abstract] Components of Income Tax Expense (Benefit), Continuing Operations [Abstract] Current: [Abstract] Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Current Federal Tax Expense (Benefit) State Current State and Local Tax Expense (Benefit) Total current taxes Current Income Tax Expense (Benefit) Deferred: [Abstract] Deferred Income Tax Expense (Benefit), Continuing Operations [Abstract] Federal Deferred Federal Income Tax Expense (Benefit) State Deferred State and Local Income Tax Expense (Benefit) Total deferred taxes Deferred Income Tax Expense (Benefit) Amortization of investment tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Investment, Amount Total income tax expense Uncertain tax positions [Abstract] Income Tax Uncertainties [Abstract] Net liability for unrecognized tax benefits inclusive of interest, penalties and net of secondary impacts which are a component of the deferred income taxes and are benefits Net liability for recognized tax benefits inclusive of interest, penalties and net of secondary impacts which are a component of the Deferred income taxes Net liability for recognized tax benefits inclusive of interest, penalties and net of secondary impacts which are a component of the Deferred income taxes Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Table] Disposal Groups, Including Discontinued Operations [Table] Disposal Group Name [Axis] Disposal Group Name [Axis] Disposal Groups, Including Discontinued Operations, Name [Domain] Disposal Group Name [Domain] Vectren Fuels, Inc. [Member] Vectren Fuels, Inc. [Member] Vectren Fuels, Inc. [Member] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] Cash received at closing Proceeds from Divestiture of Businesses Disposal Group, Including Discontinued Operation, Other Expense Disposal Group, Including Discontinued Operation, Other Expense Disposal Group, Including Discontinued Operation, Depreciation and Amortization Disposal Group, Including Discontinued Operation, Depreciation and Amortization Net income (loss) Stockholders' Equity Note [Abstract] Common Shareholder's Equity Stockholders' Equity Note Disclosure [Text Block] Schedule of Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate by Type [Axis] Change in Accounting Estimate, Type [Domain] Change in Accounting Estimate, Type [Domain] Change in Accounting Method Accounted for as Change in Estimate [Member] Change in Accounting Method Accounted for as Change in Estimate [Member] Subsegments [Axis] Subsegments [Axis] Subsegments [Domain] Subsegments [Domain] Infastructure Services [Member] Infastructure Services [Member] Segments [Axis] Property, Plant and Equipment by Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Gas Utility Plant [Member] Natural Gas Processing Plant [Member] Electric Utility Plant [Member] Electricity Generation Plant, Non-Nuclear [Member] Common Utility Plant [Member] Common Utility Plant [Member] Plant used in connection with both electric transmission and distribution and natural gas operations Construction Work in Progress [Member] Construction in Progress [Member] Computer Hardware and Software [Member] Computer Equipment [Member] Land and Buildings [Member] Land, Buildings and Improvements [Member] Vehicles and Equipment [Member] Vehicles [Member] All Other [Member] Other Capitalized Property Plant and Equipment [Member] Jointly Owned Utility Plant [Axis] Jointly Owned Utility Plant [Axis] Jointly Owned Utility Plant [Domain] Jointly Owned Utility Plant [Domain] Warrick Power Plant [Member] Warrick Power Plant [Member] Warrick Power Plant [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Utility & Nonutility Plant Property, Plant and Equipment, Net, by Type [Abstract] Original Cost Depreciation Rates as a Percent of Original Cost (in hundredths) Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service Cost of Non-Utility plant, net of depreciation and amortization Size of Unit 4 Warrick Power Plant (in megawatts) Power Plant Maximum Capacity Power Plant Maximum Capacity Southern Indiana Gas And Electric Company's Share Of Cost Of Unit 4 Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service Southern Indiana Gas And Electric Company's Share Of Accumulated Depreciation Of Unit 4 Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation Nonutility plant accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Capitalized interest on nonutility plant construction projects Interest Costs Capitalized Depreciation Depreciation Summary of components of net periodic benefit cost Schedule of Costs of Retirement Plans [Table Text Block] Schedule of assumptions used Schedule of Assumptions Used [Table Text Block] Schedule of changes in projected benefit obligations Schedule of Changes in Projected Benefit Obligations [Table Text Block] Schedule of changes in fair value of plan assets Schedule of Changes in Fair Value of Plan Assets [Table Text Block] Fair values of pension and other retirement plan assets by category and fair value hierarchy Schedule of Defined Benefit Plans Disclosures [Table Text Block] Schedule of effect of significant unobservable inputs, changes in plan assets Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets [Table Text Block] Schedule of net funded status of plans Schedule of Net Funded Status [Table Text Block] Schedule of net periodic benefit cost not yet recognized Schedule of Net Periodic Benefit Cost Not yet Recognized [Table Text Block] Reconciliation of the amounts in Accumulated other comprehensive income (AOCI) and Regulatory assets related to retirement plan obligations Schedule of Amounts Recognized in Other Comprehensive Income (Loss) [Table Text Block] Schedule of Multiemployer Contributions In Current Year [Table Text Block] Schedule of Multiemployer Plans [Table Text Block] Business Combination Disclosure [Text Block] Business Combination Disclosure [Text Block] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Corporate and Other [Member] Corporate and Other [Member] Eliminations [Member] Intersegment Eliminations [Member] Electric Utility Services [Member] Electric Utility Services [Member] Eliminations, Intersegment [Member] Eliminations, Intersegment [Member] Eliminations, Intersegment [Member] Coal Mining [Member] Coal Mining [Member] Other Businesses [Member] Other Businesses [Member] Non-Cash Cost and Change in Accruals [Member] Non-Cash Cost and Change in Accruals [Member] Non-cash costs and changes in accruals related to capital expenditures. Other Operations [Member] Other Operations [Member] Other Operations [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Property, Plant and Equipment, Additions Property, Plant and Equipment, Additions Number of reporting segments Number Of Segments Number of groups the company segregates its operation into. Number of operating segments in the Nonutility Group Portion Of Indiana That Is Provided Natural Gas Distribution And Transportation Services By Gas Utility Services Segment Portion Of Indiana That Is Provided Natural Gas Distribution And Transportation Services By Gas Utility Services Segment The percentage of Indiana that is provided natural gas distribution and transportation services by the Gas Utility Services segment. Revenues Amounts Included in Profitability Measures [Abstract] Segment Reporting, Measurement Disclosures [Abstract] Depreciation and Amortization Interest Expense Income Taxes Assets Related Party Transaction, Expenses from Transactions with Related Party Related Party Transaction, Expenses from Transactions with Related Party Reported net income (Numerator for diluted earnings per share) Net Income (Loss) Available to Common Stockholders, Diluted Weighted average common shares outstanding (Basic earnings per share) (in shares) Adjusted weighted average shares outstanding and assumed conversions outstanding (Diluted earnings per share) (in shares) Summary of inventories Schedule of Utility Inventory [Table Text Block] Summary of prepayments and other current assets Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Table Text Block] Schedule of investments in unconsolidated affiliates Schedule of Investments in and Advances to Affiliates, Schedule of Investments [Table Text Block] Other utility and corporate investments in the consolidated balance sheets Other utility and corporate investments in the consolidated balance sheets [Table Text Block] Tabular disclosure of other utility and corporate investments. Goodwill by operating segment Schedule of Goodwill [Table Text Block] Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Asset retirement obligation Schedule of Asset Retirement Obligations [Table Text Block] Equity in earnings (losses) of unconsolidated affiliates Equity Method Investments [Table Text Block] Other, net in the consolidated statements of income Schedule of Other Nonoperating Income (Expense) [Table Text Block] Supplemental cash flow information Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Operating revenues Operating income Earnings per share [Abstract] Earnings Per Share, Basic and Diluted [Abstract] Basic Accumulated Other Comprehensive Income (Loss) [Table] Accumulated Other Comprehensive Income (Loss) [Table] Deferred Income Taxes [Member] Deferred Income Taxes [Member] Deferred Income Taxes [Member] Pension and Other Benefit Costs [Member] Pension and Other Benefit Costs [Member] Pension and other benefit costs provided to a retiree (or beneficiary), usually as a function of one or more factors such as age, years of service, or compensation and postretirement benefits in terms of monetary amounts or benefit coverage to be provided. Accumulated Other Comprehensive Income (Loss) [Line Items] Accumulated Other Comprehensive Income (Loss) [Line Items] Balance, beginning of period Changes during period Balance, end of period Utility and Nonutility Plant Property, Plant and Equipment Disclosure [Text Block] Electric Rate and Regulatory Matters Public Utilities, General Disclosures - Electric [Text Block] Public Utilities, General Disclosures - Electric [Text Block] Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to cash from operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Deferred income taxes and investment tax credits Deferred Income Taxes and Tax Credits Provision for uncollectible accounts Provision for Doubtful Accounts Expense portion of pension and postretirement benefit cost Pension and Other Postretirement Benefit Expense Other non-cash charges - net Other Operating Activities, Cash Flow Statement Loss on Sale of Business (pretax) Gain (Loss) on Disposition of Business Gain on Revaluation of Contingent Consideration Business Combination, Contingent Consideration Arrangements, Change in Amount of Contingent Consideration, Liability Changes in working capital accounts: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable & accrued unbilled revenues Increase (Decrease) in Receivables Inventories Increase (Decrease) in Inventories Recoverable/refundable fuel and natural gas costs Increase (Decrease) in Recoverable Refundable Gas Costs Prepayments and other current assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable, including to affiliated companies Increase (Decrease) in Accounts Payable Accrued liabilities Increase (Decrease) in Accrued Liabilities Employer contributions to pension and postretirement plans Pension and Other Postretirement Benefit Contributions Changes in noncurrent assets Increase (Decrease) in Other Operating Assets Changes in noncurrent liabilities Increase (Decrease) in Other Operating Liabilities Net cash flows from operating activities Net Cash Provided by (Used in) Operating Activities CASH FLOWS FROM FINANCING ACTIVITIES Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from: Proceeds From Financing Activities [Abstract] Long-term debt, net of issuance costs Proceeds from Issuance of Long-term Debt Dividend reinvestment plan and other common stock issuances Proceeds from Issuance of Shares under Incentive and Share-based Compensation Plans, Including Stock Options Requirements for: Requirements For Financing Activities [Abstract] Dividends on common stock Payments of Ordinary Dividends, Common Stock Retirement of long-term debt Repayments of Long-term Debt Other financing activities Proceeds from (Payments for) Other Financing Activities Net change in short-term borrowings Proceeds from (Repayments of) Short-term Debt Net cash flows from financing activities Net Cash Provided by (Used in) Financing Activities CASH FLOWS FROM INVESTING ACTIVITIES Net Cash Provided by (Used in) Investing Activities [Abstract] Proceeds from: Proceeds from Investing Activities [Abstract] Sale of business Sale of Assets and Other collections Proceeds from Collection of Other Receivables Requirements for: Requirements For Investing Activities [Abstract] Capital expenditures, excluding AFUDC equity Payments to Acquire Property, Plant, and Equipment Business Acquisitions and Other Costs Payments to Acquire Businesses, Net of Cash Acquired Changes in Restricted Cash Increase (Decrease) in Restricted Cash Net cash flows from investing activities Net Cash Provided by (Used in) Investing Activities Net change in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets [Axis] Indefinite-lived Intangible Assets, Major Class Name [Domain] Indefinite-lived Intangible Assets, Major Class Name [Domain] Customer Related Assets [Member] Customer Related Assets [Member] Information about assets related to customers such as customer lists, relationships, etc. Market Related Assets [Member] Market Related Assets [Member] Represents 1/2 of the value of the Miller Pipeline trademark name. Indefinite-lived Intangible Assets [Line Items] Indefinite-lived Intangible Assets [Line Items] Non-amortizing Indefinite-Lived Intangible Assets (Excluding Goodwill) Schedule of Finite-Lived Intangible Assets [Table] Schedule of Finite-Lived Intangible Assets [Table] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Amortizing Finite-Lived Intangible Assets, Net Weighted average remaining life for amortizing customer-related assets and all amortizing intangibles (in years) Finite-Lived Intangible Asset, Useful Life Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Amortization expense Amortization of Intangible Assets Amortization expense - year one Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months Amortization expense - year two Finite-Lived Intangible Assets, Amortization Expense, Year Two Amortization expense - year three Finite-Lived Intangible Assets, Amortization Expense, Year Three Amortization expense - year four Finite-Lived Intangible Assets, Amortization Expense, Year Four Amortization expense - year five Finite-Lived Intangible Assets, Amortization Expense, Year Five Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] Accounting Changes and Error Corrections [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2015-03 [Member] Accounting Standards Update 2015-03 [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Impact on Regulatory Assets [Member] Impact on Regulatory Assets [Member] Impact on Regulatory Assets [Member] Other Assets [Member] Other Assets [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification, Debt Issuance Costs New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification Short term borrowing arrangements Schedule of Short-term Debt [Table Text Block] Long term senior unsecured obligations and first mortgage bonds outstanding by subsidiary Schedule of Long-term Debt Instruments [Table Text Block] Income Taxes Income Tax Disclosure [Text Block] Borrowing Arrangements Debt Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Dividends (in dollars per share) Common Stock, Dividends, Per Share, Declared Statement, Equity Components [Axis] Common Stock [Member] Common Stock [Member] Retained Earnings [Member] Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) [Member] AOCI Attributable to Parent [Member] Balance at beginning of period Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Balance at beginning of period (in shares) Comprehensive income: Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Other comprehensive income (loss) Cash flow hedges: Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax [Abstract] Common stock: Common Stock [Abstract] Issuance: option exercises and dividend reinvestment plan (in shares) Stock Issued During Period Shares Stock Options Exercised And Dividend Reinvestment Plan Number of shares issued during the period as a result of the exercise of stock options and from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity. Issuance: option exercised and dividend reinvestment plan Stock Issued During Period Value Stock Options Exercised And Dividend Reinvestment Plan Value stock issued during the period as a result of the exercise of stock options and from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity. Dividends ($1.460, $1.540 and $1.620 per share) Dividends, Common Stock, Cash Other Stockholders' Equity, Other Balance at end of period Balance at end of period (in shares) Schedule of Multiemployer Plans [Table] Schedule of Multiemployer Plans [Table] Multiemployer Plan Type [Axis] Multiemployer Plan Type [Axis] Multiemployer Plans Type [Domain] Multiemployer Plans Type [Domain] Multiemployer Plans, Pension [Member] Multiemployer Plans, Pension [Member] Multiemployer Plan Name [Axis] Multiemployer Plan Name [Axis] Multiemployer Plan Name [Domain] Multiemployer Plan Name [Domain] Central Pension Fund [Member] Central Pension Fund [Member] Central Pension Fund [Member] Pipeline Industry Benefit Fund [Member] Pipeline Industry Benefit Fund [Member] Pipeline Industry Benefit Fund [Member] Indiana Laborers Pension Fund [Member] Indiana Laborers Pension Fund [Member] Indiana Laborers Pension Fund [Member] Ohio Operating Engineers Pension Fund [Member] Ohio Operating Engineers Pension Fund [Member] Ohio Operating Engineers Pension Fund [Member] Minnesota Laborers Pension Fund [Member] Minnesota Laborers Pension Fund [Member] Minnesota Laborers Pension Fund [Member] Laborers District Fund of Ohio [Member] Laborers District Fund of Ohio [Member] Laborers District Fund of Ohio [Member] Other Pension Funds [Member] Other Pension Funds [Member] Other Pension Funds [Member] Multiemployer Plans [Line Items] Multiemployer Plans [Line Items] Approximate number of unions the Company contributed to on behalf of employees Approximate number of unions the Company contributed to on behalf of employees The approximate number of unions the Company contributed to during the year on behalf of employees Average contributions to each union Multiemployer Plans Average Contributions The average contribution made by the Company to unions within multiemployer plans during the period. Largest union multiemployer plan contribution Multiemployer Plans Largest Contribution The largest contribution made by the Company to a single union multiemployer plan during the period. Number of multiemployer plans contributed to Number of multiemployer plans contributed to Number of multi-employer plans contributed to Expense for the Multiemployer Benefit plan Multiemployer Plan, Period Contributions Defined benefit plan, number of significant plans Defined benefit plan, number of significant plans Defined benefit plan, number of significant plans Number of plans in red zone status receiving company contributions Defined benefit plan, number of plans in red zone status receiving company contributions Defined benefit plan, number of plans in red zone status receiving company contributions Number of plans in red zone status considered significant by the Company Number of plans in red zone status considered significant by the Company Number of plans in red zone status considered significant by the Company Number of plans whereby company contributions exceed 5% of plan balance Defined benefit plan, number of plans whereby company contributions exceed 5% of plan balance Number of plans whereby company contributions exceed 5% of plan balance Percentage threshold by which plan contributions are considered significant Defined benefit plan, percentage threshold by which plan contributions are considered significant Percentage threshold in which plan contributions are considered significant Multiemployer Plan, Funded Ratio Multiemployer Plan, Funded Ratio Multiemployer Plan, Funded Ratio Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Table] Defined Benefit Plans and Other Postretirement Benefit Plans Disclosures [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Axis] Defined Benefit Plans and Other Postretirement Benefit Plans [Domain] Defined Benefit Plan and Other Postretirement Benefit Plan [Domain] Other Pension Plans, Defined Benefit [Member] Other Pension Plan [Member] Other Postretirement Benefit Plans, Defined Benefit [Member] Other Postretirement Benefit Plan [Member] Defined Benefit Plan, Fair Value of Plan Assets by Measurement [Axis] Fair Value, Hierarchy [Axis] Fair Value Plan Asset Measurement [Domain]