Document And Entity Information rgco_RngRiderImpactToCustomers RNG Rider Impact to Customers The impact to customers after adjustments. UTILITY PROPERTY: Statistical Measurement [Axis] Note To Financial Statement Details Textual New Term Note 2 [Member] New Term Note 2 Note 2 - Revenue New Term Note 1 [Member] New Term Note 1 Note 3 - Segment Information INCOME TAX EXPENSE Pension Plan [Member] ecd_NonRule10b51ArrTrmntdFlag Non-Rule 10b5-1 Arrangement Terminated [Flag] Note 5 - Other Investments Variable Rate Term Note 3 [Member] Variable Rate Term Note 3 ecd_NonRule10b51ArrAdoptedFlag Non-Rule 10b5-1 Arrangement Adopted [Flag] Note 7 - Long-Term Debt us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet Utility property, net Trading Arrangements, by Individual [Table] Note 9 - Fair Value Measurements Retirement Benefits [Text Block] Material Terms of Trading Arrangement [Text Block] Note 10 - Earnings Per Share Note 11 - Other Comprehensive Income (Loss) Note 12 - Income Taxes Note 13 - Regulatory Assets and Liabilities Note 15 - Employee Benefit Plans Unsecured Term Note Payable at Term SOFR Plus 1.55%, Due September 5, 2032 2 [Member] Unsecured Term Note Payable at Term SOFR Plus 1.55%, Due September 5, 2032 2 Minimum [Member] Note 16 - Leases Product and Service, Other [Member] Unsecured Term Note Payable at Term SOFR Plus 1.55%, Due September 5, 2032 [Member] Unsecured Term Note Payable at Term SOFR Plus 1.55%, Due September 5, 2032 Note 2 - Revenue - Disaggregation of Revenue (Details) Statistical Measurement [Domain] Boost Revolving Credit Facility [Member] Boost Revolving Credit Facility Note 2 - Revenue - Customer Accounts Receivable (Details) Maximum [Member] Southgate Revolving Credit Facility [Member] Southgate Revolving Credit Facility Note 3 - Segment Information - Segment Information (Details) One Point Eight Five Note [Member] One Point Eight Five Note Note 5 - Other Investments - Schedule of Other Investments (Details) rgco_DebtInstrumentAnnualFee Debt Instrument, Annual Fee The percent amount of the annual fee payable on the debt instrument. Equity in earnings of unconsolidated affiliates Equity in earnings of unconsolidated affiliates Equity in earnings Note 5 - Other Investments - Investment in Unconsolidated Entity (Details) Note 7 - Long-Term Debt - Long-term Debt (Details) Three Point Six Five Note [Member] Three Point Six Five Note us-gaap_DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year Note 7 - Long-Term Debt - Long-term Debt (Details) (Parentheticals) Increase (decrease) in Trade accounts receivable Retirement Plan Type [Domain] Four M Swap [Member] Four M Swap Note 9 - Fair Value Measurements - Schedule of Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis (Details) Note 9 - Fair Value Measurements - Summary of the Fair Value of Financial Assets and Liabilities Not Adjusted to Fair Value (Details) New Term Notes [Member] New Term Notes Note 10 - Earnings Per Share - Earnings Per Share (Details) Retirement Plan Type [Axis] Twenty Point Six M Swap [Member] Twenty Point Six M Swap Note 11 - Other Comprehensive Income (Loss) - Schedule of Other Comprehensive Income and Loss (Details) Note 11 - Other Comprehensive Income (Loss) - Reconciliation of Accumulated Comprehensive Income (Loss) (Details) Note 12 - Income Taxes - Income Positions (Details) us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses Recognized loss Note 13 - Regulatory Assets and Liabilities - Schedule of Regulatory Assets (Details) Note 13 - Regulatory Assets and Liabilities - Schedule of Regulatory Liabilities (Details) Note 15 - Employee Benefit Plans - Schedule of Components of Net Periodic Pension and Postretirement Benefit Cost (Details) Note 16 - Leases - Lease Cost (Details) Note 16 - Leases - Operating Lease Maturity (Details) Notes To Financial Statements Notes To Financial Statements [Abstract] Effective tax rate us-gaap_DefinedBenefitPlanContributionsByEmployer Defined Benefit Plan, Plan Assets, Contributions by Employer Income Tax Jurisdiction [Domain] us-gaap_DividendsCommonStockCash Cash dividends declared Interest cost us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets Expected return on plan assets Dividends declared per share (in dollars per share) Dividends declared per share (in dollars per share) us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost Net periodic pension cost Boost [Member] Represents Boost. MVP Southgate Note 1 [Member] MVP Southgate Note 1 Service cost MVP Southgate Notes [Member] MVP Southgate Notes Regulation Status [Axis] Segment Reporting [Text Block] Interest Rate Upon Meeting Milestones [Member] Interest Rate Upon Meeting Milestones Two Interest Rate Swaps [Member] Two Interest Rate Swaps Segment Reporting [Table Text Block] Adjustments to reconcile net income to net cash provided by operating activities: Preferred stock, no par, authorized 5,000,000 shares; no shares issued and outstanding Defined Benefit Plan [Table] Schedule of Regulatory Liabilities [Table Text Block] Consolidation Items [Axis] Total liabilities and equity us-gaap_LiabilitiesAndStockholdersEquity TOTAL LIABILITIES AND STOCKHOLDERS’ EQUITY Schedule of Regulatory Assets [Table Text Block] rgco_ResearchTaxCreditsSettlementPercentage Research Tax Credits, Settlement, Percentage The percent settlement on the research tax credits. Segment Reporting [Table] us-gaap_ShareBasedCompensation Stock-based compensation Subsequent Event [Member] Consolidation Items [Domain] Equity Method Investment, Nonconsolidated Investee [Axis] Equity Method Investment, Nonconsolidated Investee [Domain] Accumulated Defined Benefit Plans Adjustment, Net Gain (Loss) Attributable to Parent [Member] us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationTax Net interest rate swaps, tax Net interest rate swaps, before tax us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax Interest rate swaps us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax Net interest rate swaps, after tax Lessee, Lease, Description [Table] us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax Unrealized gains (losses), after tax us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax Unrealized gains (losses), tax Unrealized gains (losses), before tax Lease Contractual Term [Axis] Transfer of realized gains to interest expense, tax Lease Contractual Term [Domain] us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationBeforeTax Transfer of realized gains to interest expense, before tax us-gaap_OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax Transfer of realized gains to interest expense, after tax Preferred stock, shares issued (in shares) Preferred stock, shares outstanding (in shares) us-gaap_IncreaseDecreaseInOperatingCapital Changes in assets and liabilities which (used) provided cash, exclusive of changes and noncash transactions shown separately Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent [Member] Preferred stock, shares authorized (in shares) Portion at Fair Value Measurement [Member] Reported Value Measurement [Member] us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect NET INCREASE IN CASH AND CASH EQUIVALENTS Cash and cash equivalents Estimate of Fair Value Measurement [Member] rgco_EnergyRelatedInventoryNaturalGasInStoragePortionRemoved Energy Related Inventory, Natural Gas in Storage, Portion Removed The carrying amount of the portion of natural gas in storage that was removed, which is a mixture of gases (liquefied or otherwise), used for fuel and manufacturing purposes. us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations BEGINNING CASH AND CASH EQUIVALENTS ENDING CASH AND CASH EQUIVALENTS Statement [Table] Credit Facility [Axis] Cash paid on operating leases Credit Facility [Domain] Revolving Credit Facility [Member] Prepaid income taxes Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Basis spread Debt Instrument, Basis Spread on Variable Rate Right of use obtained in exchange for operating lease obligations us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity Line of Credit Facility, Maximum Borrowing Capacity Unsecured term note payable, at Term SOFR plus 1.00%, due October 1, 2028 [Member] Represents unsecured term note payable, at Term SOFR plus 1.00%, due October 1, 2028. us-gaap_NotesPayableFairValueDisclosure Notes payable us-gaap_EquityMethodInvestmentOwnershipPercentage Equity Method Investment, Ownership Percentage Long-Term Debt, Type [Axis] Product and Service [Domain] Product and Service [Axis] Revolving credit facility us-gaap_LineOfCredit Long-Term Line of Credit Line-of-credit Line of Credit Facility [Table] Thereafter, rental payments us-gaap_LesseeOperatingLeaseLiabilityPaymentsDue Total minimum lease payments Property, plant and equipment, net In service, net Period end net book value of property, plant and equipment that is in service and owned by the regulated operations of the public utility. MVP Boost Note [Member] Represents the MVP boost debt note. Weighted-average discount rate us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths 2026, rental payments us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFive 2030, rental payments Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearThree 2028, rental payments Measurement Frequency [Axis] Commitments and Contingencies Disclosure [Text Block] us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearTwo 2027, rental payments Statement [Line Items] us-gaap_LesseeOperatingLeaseLiabilityPaymentsDueYearFour 2029, rental payments Fair Value Hierarchy and NAV [Axis] Common stock, shares issued (in shares) Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Common stock, shares outstanding (in shares) Common stock, shares authorized (in shares) Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Common stock, $5 par; authorized 20,000,000 shares; issued and outstanding 10,418,255 and 10,338,308 shares, respectively us-gaap_ProceedsFromIssuanceOfCommonStock Proceeds from issuance of stock Accounts payable us-gaap_PolicyTextBlockAbstract Accounting Policies us-gaap_DisclosureTextBlockAbstract Notes to Financial Statements us-gaap_TableTextBlock Notes Tables Comprehensive Income (Loss) Note [Text Block] Borrowings under line-of-credit us-gaap_ComprehensiveIncomeNetOfTax COMPREHENSIVE INCOME Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] Subsequent Events [Text Block] us-gaap_SegmentExpenditureAdditionToLongLivedAssets Gross additions to utility property Concentration Risk Type [Axis] us-gaap_AccruedLiabilitiesCurrent Accrued expenses Dividends payable Significant Accounting Policies [Text Block] rgco_EstimateOfPossibleDamagesRelatedToLngTankDamages Estimate of Possible Damages Related to LNG Tank Damages The amount of estimated possible damages related to the LNG tank damages. us-gaap_LesseeOperatingLeaseLiabilityUndiscountedExcessAmount Less imputed interest us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount Public Utilities, Requested Rate Increase (Decrease), Amount Total Public Utilities General Disclosures [Table] us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount Public Utilities, Approved Rate Increase (Decrease), Amount Accounts Receivable [Member] Current maturities of long-term debt Current maturities of long-term debt Less: current maturities of long-term debt Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Concentration Risk Type [Domain] Schedule of Regulatory Assets and Liabilities [Text Block] us-gaap_LongTermDebtNoncurrent Long-term debt, net us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage Public Utilities, Approved Return on Equity, Percentage Construction work in progress us-gaap_PublicUtilitiesApprovedEquityCapitalStructurePercentage Public Utilities, Approved Equity Capital Structure, Percentage Income Tax Jurisdiction, Domestic Federal [Member] Proceeds from disposal of utility property Three Other Operating Leases [Member] Represents three other operating leases. Income Tax Jurisdiction, Domestic State and Local [Member] Investment in unconsolidated affiliates Investment in unconsolidated affiliates LONG-TERM DEBT: us-gaap_OtherComprehensiveIncomeLossBeforeTaxPortionAttributableToParent Other comprehensive income (loss), before tax rgco_EffectiveIncomeTaxRateReconciliationAtFederalAndStateStatutoryIncomeTaxRatePercent Effective Income Tax Rate Reconciliation, at Federal and State Statutory Income Tax Rate, Percent Percentage of the combined domestic federal and state statutory tax rate applicable to pretax income (loss). rgco_DebtInstrumentDebtCovenantInterestCoverageRatio Debt Instrument, Debt Covenant, Interest Coverage Ratio Represents the interest coverage ratio requirement. Other comprehensive income (loss), net of tax: Statement of Stockholders' Equity [Abstract] Loss Contingency Nature [Axis] Statement of Comprehensive Income [Abstract] Capital contributions payable Carrying value as of the balance sheet date of liabilities incurred and payable for capital contributions that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Supplier Refund [Member] Represents rate action of a regulator resulting in capitalization or accrual of supplier refund. Statement of Cash Flows [Abstract] us-gaap_OtherComprehensiveIncomeDefinedBenefitPlansAdjustmentNetOfTaxPortionAttributableToParent Defined benefit plans Regulatory cost of retirement obligations Regulatory cost of retirement obligations Regulatory cost of retirement obligations not otherwise included in ARO. Other comprehensive loss Other comprehensive income OTHER COMPREHENSIVE INCOME (LOSS), NET OF TAX Other comprehensive income (loss), after tax Long-Term Debt, Type [Domain] STOCKHOLDERS’ EQUITY: Cost of retirement of utility property Cost incurred to retire and remove from service property of the entity including amount to settle asset retirement obligations. Equity Components [Axis] Residential [Member] Related to residential. Commercial [Member] Related to commercial. Proceeds from issuance of unsecured notes Gas Utility [Member] Related to gas utility. Non-utility [Member] Related to non-utility. Equity Component [Domain] RGC Midstream LLC [Member] Related to RGC Midstream LLC. MVP [Member] Related to MVP. Fair Value, Inputs, Level 2 [Member] rgco_ChangeInInvestmentInUnconsolidatedAffiliate Change in investment in unconsolidated affiliates The amount of change in investment in unconsolidated affiliate. Fair Value, Inputs, Level 3 [Member] AOCI Attributable to Parent [Member] Alternative revenue programs The amount of revenue from alternative revenue programs. Fair Value, Inputs, Level 1 [Member] Additional Paid-in Capital [Member] Increase (decrease) in Customer deposits Amount of increase (decrease) of liability for consideration received or receivable from customer which is not included in the transaction price, when considered is expected to be refunded to customer. Retained Earnings [Member] AFUDC rgco_IncomeFromAllowanceForFundsUsedDuringConstruction The amount of income from allowance for funds used during construction. Roanoke Gas Company [Member] Related to the Roanoke Gas Company. Cost of gas and sale Cost of gas - utility Unsecured Term Notes [Member] Related to unsecured term notes. Loss Contingency, Nature [Domain] Southgate [Member] Related to Southgate. Change in accrued capital calls The noncash increase (decrease) in unconsolidated affiliate. The noncash change reflects the affect of fluctuations in capital contributions payable during the related period. Unsecured Term Notes Payable, at 3.58%, Due on October 2, 2027 [Member] Related to debt. Unsecured Term Notes Payable, at 4.41 %, Due on March 28, 2031 [Member] Related to debt. Unsecured Term Notes Payable, at 3.60%, Due on December 6, 2029 [Member] Related to debt. Benefit plan assets Benefit plan liabilities Unsecured Senior Notes Payable, at 4.26%, Due on September 18, 2034 [Member] Related to debt. Subsequent Event Type [Domain] Subsequent Event [Table] Subsequent Event Type [Axis] us-gaap_DeferredIncomeTaxAssetsNet Deferred income taxes Comprehensive Income (Loss) [Table Text Block] Schedule of Net Benefit Costs [Table Text Block] Public Utilities Disclosure [Text Block] Unsecured Senior Notes Payable [Member] Related to unsecured senior notes payable. us-gaap_DeferredIncomeTaxLiabilitiesNet Deferred income taxes Fair Value Disclosures [Text Block] Fair Value, by Balance Sheet Grouping [Table Text Block] SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION: CURRENT LIABILITIES: Current liabilities us-gaap_LiabilitiesCurrent Total current liabilities In service us-gaap_RemainingAmountsOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided Remaining Amounts of Regulatory Assets for which No Return on Investment During Recovery Period is Provided Accounts receivable (less allowance for credit losses of $576,431 and $142,911, respectively) Trade accounts receivable Other Regulatory Assets (Liabilities) [Member] Customer Concentration Risk [Member] Unsecured Delayed-draw Term Note Payable at Term SOFR Plus 1.00%, Due August 20, 2029 [Member] The unsecured delayed-draw term note payable at Term SOFR plus 1.00%, due August 20, 2029. Construction work in progress us-gaap_PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress Unsecured Delayed-draw Promissory Note [Member] The unsecured delayed-draw Promissory Note. Unsecured Delayed-draw Term Note Payable [Member] The unsecured delayed-draw term note payable. us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation Accumulated depreciation and amortization LNG Tank Damage Cost Estimate [Member] The LNG Tank damage cost estimate. Deferred LNG Facility Costs [Member] The deferred LNG facility costs. LNG Tank [Member] The LNG tank. Lease, Cost [Table Text Block] Long-Term Debt [Text Block] Other Commitments [Table] Accumulated other comprehensive income us-gaap_IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest Income before income taxes INCOME BEFORE INCOME TAXES Cash investment Investment in unconsolidated affiliates Gross investment in affiliates Capital in excess of par value Debt Disclosure [Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] us-gaap_PaymentsToAcquirePropertyPlantAndEquipment Additions to utility property Net issuance of common stock Lessee, Operating Leases [Text Block] us-gaap_DebtInstrumentFaceAmount Debt Instrument, Face Amount CURRENT ASSETS: Current assets Total current assets us-gaap_RegulatoryAssetAmortizationPeriod Regulatory Asset, Amortization Period (Year) OPERATING EXPENSES: rgco_AssetManagementContractTerm Asset Management Contract Term (Year) Represents asset management contract term. Common stock issued (in shares) Debt Instrument, Name [Domain] Stated rate Distributions from unconsolidated affiliate Proceeds from Equity Method Investment, Distribution Distributions from unconsolidated affiliate Schedule of Long-Term Debt Instruments [Table] Debt Instrument [Axis] CASH FLOWS FROM OPERATING ACTIVITIES: Inventories CASH FLOWS FROM INVESTING ACTIVITIES: us-gaap_NetCashProvidedByUsedInOperatingActivities Net cash provided by operating activities CASH FLOWS FROM FINANCING ACTIVITIES: us-gaap_NetCashProvidedByUsedInInvestingActivities Net cash used in investing activities us-gaap_PaymentsOfDebtIssuanceCosts Debt issuance expenses us-gaap_NetCashProvidedByUsedInFinancingActivities Net cash used in financing activities Total Liabilities fair value Total Liabilities fair value Total Assets fair value Natural gas purchases Fair market value estimated at the corresponding first of month index prices for which the obligation, the timing difference between the payment for natural gas purchases and the actual receipt of such purchases under the current asset management contract, is expected to be settled. WNA [Member] Related to WNA. Operating Segments [Member] Under-recovery of SAVE Plan Revenues [Member] Related to under-recovery of SAVE plan revenues. Accounting Policies [Abstract] Segments [Domain] rgco_RngRiderRevenueRequirement RNG Rider Revenue Requirement The gross revenue for the RNG rider program. Investment in Affiliates [Member] Related to investment in affiliates. Accounts Receivable, allowance for uncollectible rgco_RegulatoryLiabilitiesAndAssetRetirementObligationsNoncurrent Total non-current The amount of regulatory liabilities and asset retirement obligations classified as noncurrent. us-gaap_UnamortizedDebtIssuanceExpense Unamortized debt issuance costs Unamortized debt issuance costs Segments [Axis] Regulatory Clause Revenues, under-Recovered [Member] Internal Revenue Service (IRS) [Member] Income Statement [Abstract] us-gaap_NumberOfReportableSegments Number of Reportable Segments Other us-gaap_OtherAssetsMiscellaneousNoncurrent us-gaap_UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Net income Net income NET INCOME NET INCOME DEFERRED CREDITS AND OTHER NON-CURRENT LIABILITIES: Virginia, Jurisdiction [Member] Designated tax department of a state or local government entitled to levy and collect income taxes from the entity. rgco_SAVEAnnualRevenues SAVE Annual Revenues The represented annual revenues under the SAVE program. Regulatory Asset [Axis] Deferred Gain (Loss) on Early Extinguishment of Debt [Member] Regulated and Unregulated Operation [Domain] Total regulatory assets Total long-term debt, net current maturities us-gaap_UnsecuredLongTermDebt Notes payable Accumulated Other Comprehensive Income (Loss) [Table] Unsecured Debt [Member] us-gaap_CostsAndExpenses Total operating expenses Notes payable us-gaap_UnsecuredDebt Regulatory Liability [Axis] Regulatory Liability [Domain] Regulatory liabilities us-gaap_RegulatoryLiabilities Total regulatory liabilities Income Tax Disclosure [Text Block] Regulatory assets Regulatory assets Noncurrent regulatory assets Regulatory Asset, Noncurrent Regulatory Asset [Domain] Pension Costs [Member] Accounting Standards Update and Change in Accounting Principle [Table] Regulatory liabilities us-gaap_RegulatoryLiabilityNoncurrent Regulatory Liability, Noncurrent Operations and maintenance Operations and maintenance Inventory [Domain] Inventory [Axis] Asset retirement obligations Measurement Basis [Axis] Other Deferred Liabilities [Member] Represents other deferred liabilities. Fair Value Hierarchy and NAV [Domain] Measurement Frequency [Domain] us-gaap_OpenTaxYear Open Tax Year us-gaap_RepaymentsOfLinesOfCredit Repayments under line-of-credit Statement of Financial Position [Abstract] Noncurrent liabilities us-gaap_LiabilitiesNoncurrent Income taxes, net of refunds us-gaap_RepaymentsOfNotesPayable Repayments of notes payable Other assets Fair Value, Recurring [Member] us-gaap_OtherAssetsNoncurrent Total other non-current assets Deferred Income Tax Charge [Member] Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table] Document Type Document Information [Line Items] Document Quarterly Report us-gaap_LesseeOperatingLeaseTermOfContract Lessee, Operating Lease, Term of Contract (Year) Weighted-average remaining term (in years) (Year) Document Information [Table] us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount (in shares) Entity Interactive Data Current Document Transition Report us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding Diluted average common shares (in shares) Operating expenses us-gaap_OperatingExpenses Effect of potentially dilutive securities (in shares) Weighted-average common shares (in shares) us-gaap_WeightedAverageNumberOfSharesOutstandingBasic Derivative Instrument [Axis] Antidilutive Security, Excluded EPS Calculation [Table] Basic (in dollars per share) BASIC EARNINGS PER COMMON SHARE (in dollars per share) Earnings Per Share, Basic, by Common Class, Including Two-Class Method [Table] Effective Income Tax Rate Reconciliation [Table] us-gaap_NumberOfInterestRateDerivativesHeld Number of Interest Rate Derivatives Held Postemployment Retirement Benefits [Member] Income Tax Jurisdiction [Axis] Under-recovery of RNG Revenues [Member] Related to Under-recovery of RNG revenues. Rate Refund [Member] Related to rate refund. Document Fiscal Period Focus rgco_RecoveryCostsSaveEligibleExpenses Recovery Costs, SAVE Eligible Expenses Represents the recovery costs associated with SAVE eligible expenses. Customer [Domain] Document Fiscal Year Focus Investment, Name [Domain] Depreciation and amortization Depreciation and amortization Amendment Flag Common Stock [Member] Unsecured Revolving Note Maturing March 31, 2024 [Member] Represents the unsecured revolving note maturing March 31, 2024. Document Period End Date Investment [Table Text Block] Amended and Restated Delayed Term Note Entered September 24, 2021 [Member] Represents the amended and restated delayed term note entered into on September 24, 2021. Legal Entity [Axis] Subsequent Letter of Commitment to Refinance [Member] The letter of commitment that Midstream will be refinanced, subsequent to the end of the quarter. us-gaap_OperatingLeaseCost Operating Lease, Cost Entity File Number Derivative fixed interest rate Derivative, Fixed Interest Rate Entity Tax Identification Number rgco_DebtInstrumentOriginationFeePercentage Debt Instrument, Origination Fee, Percentage The percentage amount of the origination fee payable on the debt instrument. Disaggregation of Revenue [Table Text Block] Disaggregation of Revenue [Table] Entity [Domain] Entity Central Index Key Entity Registrant Name Entity Current Reporting Status Transportation and Interruptible [Member] Represents the Transportation and interruptible group. Entity Incorporation, State or Country Code Current Fiscal Year End Date Other comprehensive income (loss), tax Entity Filer Category Entity Shell Company Entity Emerging Growth Company us-gaap_DerivativeNotionalAmount Derivative, Notional Amount Entity Small Business us-gaap_OperatingIncomeLoss Operating income (loss) OPERATING INCOME us-gaap_DerivativeAssetsNoncurrent Interest rate swaps Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Interest rate swaps Interest expense Interest expense Regulated Operation, Regulatory Asset [Table] Derivative Instruments and Hedging Activities Disclosure [Text Block] Regulated Operation, Regulatory Liability [Table] Revenue Revenues Revenue Customer deposits Customer deposits Interest rate swaps - noncurrent Interest rate swaps Entity Address, State or Province Entity Address, City or Town Interest rate swaps - current Interest rate swaps Retained earnings Entity Address, Address Line One us-gaap_ContractWithCustomerAssetNetCurrent Unbilled revenue City Area Code Local Phone Number Revenue from Contract with Customer [Text Block] Entity Address, Postal Zip Code Equity Method Investment [Table] Unsecured Term Notes Payable, at 30-day SOFR Average 1.20% Due August 20, 2026 [Member] Represents the unsecured term notes payable at 30 day SOFR average 1.20% due August 20, 2026. Derivative [Table] Title of 12(b) Security Security Exchange Name Trading Symbol Class of Stock [Axis] Entity Common Stock, Shares Outstanding Earnings Per Share [Text Block] Preferred stock, par value (in dollars per share) Other us-gaap_OtherAssetsCurrent us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent Total deferred credits and other non-current liabilities Scenario [Axis] Scenario [Domain] Income taxes payable Common stock, par value (in dollars per share) Investment, Name [Axis] Taxes other than income taxes Taxes other than income taxes Derivative Contract [Domain] Other income, net Other income, net Receivable [Domain] Total assets Assets TOTAL ASSETS us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansBeforeTax Amortization of net actuarial gains, before tax Diluted (in dollars per share) DILUTED EARNINGS PER COMMON SHARE (in dollars per share) us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax Amortization of net actuarial gains, after tax Customer [Axis] Customer credit balances Customer credit balances Equity Method Investments and Joint Ventures Disclosure [Text Block] us-gaap_OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansTax Amortization of net actuarial gains, tax us-gaap_DepreciationDepletionAndAmortization Depreciation and amortization Equity Method Investments [Table Text Block] Segment Reporting, Reconciling Item, Corporate Nonsegment [Member] rgco_NumberOfMajorCustomers Number of Major Customers Represents the number of major customers accounting for 5% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc. Trade Accounts Receivable [Member] Receivable Type [Axis] Interest Interest Rate Swap [Member] rgco_DebtInstrumentDebtCovenantRatioOfLongtermDebtToTotalCapitalizationMaximum Debt Instrument, Debt Covenant Ratio of Long-term Debt to Total Capitalization, Maximum The maximum debt covenant ratio of long-term debt to total capitalization of a debt instrument. rgco_DebtInstrumentDebtCovenantRatioOfPriorityDebtToTotalAssetsMaximum Debt Instrument, Debt Covenant, Ratio of Priority Debt to Total Assets, Maximum The maximum debt covenant ratio of priority debt to total assets of a debt instrument. Gas in storage Schedule of Long-Term Debt Instruments [Table Text Block] Oil and Gas [Member] OTHER NON-CURRENT ASSETS: us-gaap_NumberOfStatesInWhichEntityOperates Number of States in which Entity Operates Capital us-gaap_StockholdersEquity Total stockholders’ equity Balance Balance Increase (decrease) in Customer credit balances Increase (decrease) in Unbilled revenue us-gaap_PaymentsOfDividendsCommonStock Cash dividends paid Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Domain] Other us-gaap_OtherLiabilitiesCurrent Other Variable Rate Term Note 2 [Member] Variable Rate Term Note 2 ecd_Rule10b51ArrTrmntdFlag Rule 10b5-1 Arrangement Terminated [Flag] us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax Total contracts with customers Variable Rate Term Note 1 [Member] Variable Rate Term Note 1 ecd_Rule10b51ArrAdoptedFlag Rule 10b5-1 Arrangement Adopted [Flag]