3.25.4 html 348 508 1 false 90 0 false 6 false false R1.htm 0000001 - Document - Audit Information Sheet http://www.onegas.com/role/AuditInformation Audit Information Cover 1 false false R2.htm 9952151 - Document - Cover Page Sheet http://www.onegas.com/role/CoverPage Cover Page Cover 2 false false R3.htm 9952152 - Statement - STATEMENTS OF INCOME Sheet http://www.onegas.com/role/STATEMENTSOFINCOME STATEMENTS OF INCOME Statements 3 false false R4.htm 9952153 - Statement - STATEMENTS OF COMPREHENSIVE INCOME Sheet http://www.onegas.com/role/STATEMENTSOFCOMPREHENSIVEINCOME STATEMENTS OF COMPREHENSIVE INCOME Statements 4 false false R5.htm 9952154 - Statement - BALANCE SHEETS Sheet http://www.onegas.com/role/BALANCESHEETS BALANCE SHEETS Statements 5 false false R6.htm 9952155 - Statement - BALANCE SHEETS Parenthetical Sheet http://www.onegas.com/role/BALANCESHEETSParenthetical BALANCE SHEETS Parenthetical Statements 6 false false R7.htm 9952156 - Statement - STATEMENTS OF CASH FLOWS Sheet http://www.onegas.com/role/STATEMENTSOFCASHFLOWS STATEMENTS OF CASH FLOWS Statements 7 false false R8.htm 9952157 - Statement - STATEMENT OF CHANGES IN EQUITY Sheet http://www.onegas.com/role/STATEMENTOFCHANGESINEQUITY STATEMENT OF CHANGES IN EQUITY Statements 8 false false R9.htm 9952158 - Disclosure - Accounting Policies Sheet http://www.onegas.com/role/AccountingPolicies Accounting Policies Notes 9 false false R10.htm 9952159 - Disclosure - REVENUE (Notes) Notes http://www.onegas.com/role/REVENUENotes REVENUE (Notes) Notes 10 false false R11.htm 9952160 - Disclosure - REGULATORY ASSETS AND LIABILITIES (Notes) Notes http://www.onegas.com/role/REGULATORYASSETSANDLIABILITIESNotes REGULATORY ASSETS AND LIABILITIES (Notes) Notes 11 false false R12.htm 9952161 - Disclosure - CREDIT FACILITIES (Notes) Notes http://www.onegas.com/role/CREDITFACILITIESNotes CREDIT FACILITIES (Notes) Notes 12 false false R13.htm 9952162 - Disclosure - LONG-TERM DEBT (Notes) Notes http://www.onegas.com/role/LONGTERMDEBTNotes LONG-TERM DEBT (Notes) Notes 13 false false R14.htm 9952163 - Disclosure - Leases Sheet http://www.onegas.com/role/Leases Leases Notes 14 false false R15.htm 9952164 - Disclosure - EQUITY (Notes) Notes http://www.onegas.com/role/EQUITYNotes EQUITY (Notes) Notes 15 false false R16.htm 9952165 - Disclosure - ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Notes) Notes http://www.onegas.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSNotes ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Notes) Notes 16 false false R17.htm 9952166 - Disclosure - EARNINGS PER SHARE (Notes) Notes http://www.onegas.com/role/EARNINGSPERSHARENotes EARNINGS PER SHARE (Notes) Notes 17 false false R18.htm 9952167 - Disclosure - Compensation Related Costs, Share Based Payments Sheet http://www.onegas.com/role/CompensationRelatedCostsShareBasedPayments Compensation Related Costs, Share Based Payments Notes 18 false false R19.htm 9952168 - Disclosure - EMPLOYEE BENEFIT PLANS (Notes) Notes http://www.onegas.com/role/EMPLOYEEBENEFITPLANSNotes EMPLOYEE BENEFIT PLANS (Notes) Notes 19 false false R20.htm 9952169 - Disclosure - INCOME TAXES (Notes) Notes http://www.onegas.com/role/INCOMETAXESNotes INCOME TAXES (Notes) Notes 20 false false R21.htm 9952170 - Disclosure - OTHER INCOME AND OTHER EXPENSE (Notes) Notes http://www.onegas.com/role/OTHERINCOMEANDOTHEREXPENSENotes OTHER INCOME AND OTHER EXPENSE (Notes) Notes 21 false false R22.htm 9952171 - Disclosure - Property, Plant, and Equipment Sheet http://www.onegas.com/role/PropertyPlantandEquipment Property, Plant, and Equipment Notes 22 false false R23.htm 9952172 - Disclosure - COMMITMENTS AND CONTINGENCIES (Notes) Notes http://www.onegas.com/role/COMMITMENTSANDCONTINGENCIESNotes COMMITMENTS AND CONTINGENCIES (Notes) Notes 23 false false R24.htm 9952173 - Disclosure - DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Notes) Notes http://www.onegas.com/role/DERIVATIVEFINANCIALINSTRUMENTSANDFAIRVALUEMEASUREMENTSNotes DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Notes) Notes 24 false false R25.htm 9952174 - Disclosure - VARIABLE INTEREST ENTITES (Notes) Notes http://www.onegas.com/role/VARIABLEINTERESTENTITESNotes VARIABLE INTEREST ENTITES (Notes) Notes 25 false false R26.htm 995445 - Disclosure - Insider Trading Arrangements Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements Insider Trading Arrangements Notes 26 false false R27.htm 995447 - Disclosure - Insider Trading Policies and Procedures Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingPoliciesProc Insider Trading Policies and Procedures Notes 27 false false R28.htm 995550 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure Sheet http://xbrl.sec.gov/cyd/role/CybersecurityRiskManagementAndStrategyDisclosure Cybersecurity Risk Management and Strategy Disclosure Notes 28 false false R29.htm 9955511 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies) Sheet http://www.onegas.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESPolicies SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies) Policies http://www.onegas.com/role/AccountingPolicies 29 false false R30.htm 9955512 - Disclosure - REVENUE (Tables) Sheet http://www.onegas.com/role/REVENUETables REVENUE (Tables) Tables http://www.onegas.com/role/REVENUENotes 30 false false R31.htm 9955513 - Disclosure - REGULATORY ASSETS AND LIABILITIES (Tables) Sheet http://www.onegas.com/role/REGULATORYASSETSANDLIABILITIESTables REGULATORY ASSETS AND LIABILITIES (Tables) Tables http://www.onegas.com/role/REGULATORYASSETSANDLIABILITIESNotes 31 false false R32.htm 9955514 - Disclosure - LONG-TERM DEBT (Tables) Sheet http://www.onegas.com/role/LONGTERMDEBTTables LONG-TERM DEBT (Tables) Tables http://www.onegas.com/role/LONGTERMDEBTNotes 32 false false R33.htm 9955515 - Disclosure - Leases, (Tables) Sheet http://www.onegas.com/role/LeasesTables Leases, (Tables) Tables http://www.onegas.com/role/Leases 33 false false R34.htm 9955516 - Disclosure - Equity (Tables) Sheet http://www.onegas.com/role/EquityTables Equity (Tables) Tables 34 false false R35.htm 9955517 - Disclosure - ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables) Sheet http://www.onegas.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSTables ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Tables) Tables http://www.onegas.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSNotes 35 false false R36.htm 9955518 - Disclosure - EARNINGS PER SHARE (Tables) Sheet http://www.onegas.com/role/EARNINGSPERSHARETables EARNINGS PER SHARE (Tables) Tables http://www.onegas.com/role/EARNINGSPERSHARENotes 36 false false R37.htm 9955519 - Disclosure - Compensation Related Costs, Share Based Payments (Tables) Sheet http://www.onegas.com/role/CompensationRelatedCostsShareBasedPaymentsTables Compensation Related Costs, Share Based Payments (Tables) Tables http://www.onegas.com/role/CompensationRelatedCostsShareBasedPayments 37 false false R38.htm 9955520 - Disclosure - EMPLOYEE BENEFIT PLANS (Tables) Sheet http://www.onegas.com/role/EMPLOYEEBENEFITPLANSTables EMPLOYEE BENEFIT PLANS (Tables) Tables http://www.onegas.com/role/EMPLOYEEBENEFITPLANSNotes 38 false false R39.htm 9955521 - Disclosure - Income Taxes (Tables) Sheet http://www.onegas.com/role/IncomeTaxesTables Income Taxes (Tables) Tables 39 false false R40.htm 9955522 - Disclosure - OTHER INCOME AND OTHER EXPENSE (Tables) Sheet http://www.onegas.com/role/OTHERINCOMEANDOTHEREXPENSETables OTHER INCOME AND OTHER EXPENSE (Tables) Tables http://www.onegas.com/role/OTHERINCOMEANDOTHEREXPENSENotes 40 false false R41.htm 9955523 - Disclosure - Property, Plant, and Equipment (Tables) Sheet http://www.onegas.com/role/PropertyPlantandEquipmentTables Property, Plant, and Equipment (Tables) Tables http://www.onegas.com/role/PropertyPlantandEquipment 41 false false R42.htm 9955524 - Disclosure - DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Tables) Sheet http://www.onegas.com/role/DERIVATIVEFINANCIALINSTRUMENTSANDFAIRVALUEMEASUREMENTSTables DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Tables) Tables http://www.onegas.com/role/DERIVATIVEFINANCIALINSTRUMENTSANDFAIRVALUEMEASUREMENTSNotes 42 false false R43.htm 9955525 - Disclosure - VARIABLE INTEREST ENTITES (Tables) Sheet http://www.onegas.com/role/VARIABLEINTERESTENTITESTables VARIABLE INTEREST ENTITES (Tables) Tables http://www.onegas.com/role/VARIABLEINTERESTENTITESNotes 43 false false R44.htm 9955526 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) Sheet http://www.onegas.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESDetails SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) Details http://www.onegas.com/role/SUMMARYOFSIGNIFICANTACCOUNTINGPOLICIESPolicies 44 false false R45.htm 9955527 - Disclosure - REVENUE (Details) Sheet http://www.onegas.com/role/REVENUEDetails REVENUE (Details) Details http://www.onegas.com/role/REVENUETables 45 false false R46.htm 9955528 - Disclosure - REGULATORY ASSETS AND LIABILITIES (Details) Sheet http://www.onegas.com/role/REGULATORYASSETSANDLIABILITIESDetails REGULATORY ASSETS AND LIABILITIES (Details) Details http://www.onegas.com/role/REGULATORYASSETSANDLIABILITIESTables 46 false false R47.htm 9955529 - Disclosure - CREDIT FACILITIES (Details) Sheet http://www.onegas.com/role/CREDITFACILITIESDetails CREDIT FACILITIES (Details) Details http://www.onegas.com/role/CREDITFACILITIESNotes 47 false false R48.htm 9955530 - Disclosure - LONG-TERM DEBT (Details) Sheet http://www.onegas.com/role/LONGTERMDEBTDetails LONG-TERM DEBT (Details) Details http://www.onegas.com/role/LONGTERMDEBTTables 48 false false R49.htm 9955531 - Disclosure - Leases (Details) Sheet http://www.onegas.com/role/LeasesDetails Leases (Details) Details http://www.onegas.com/role/LeasesTables 49 false false R50.htm 9955532 - Disclosure - EQUITY (Details) Sheet http://www.onegas.com/role/EQUITYDetails EQUITY (Details) Details http://www.onegas.com/role/EQUITYNotes 50 false false R51.htm 9955533 - Disclosure - ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) Sheet http://www.onegas.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSDetails ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Details) Details http://www.onegas.com/role/ACCUMULATEDOTHERCOMPREHENSIVEINCOMELOSSTables 51 false false R52.htm 9955534 - Disclosure - EARNINGS PER SHARE (Details) Sheet http://www.onegas.com/role/EARNINGSPERSHAREDetails EARNINGS PER SHARE (Details) Details http://www.onegas.com/role/EARNINGSPERSHARETables 52 false false R53.htm 9955535 - Disclosure - Compensation Related Costs, Share Based Payments (Details) Sheet http://www.onegas.com/role/CompensationRelatedCostsShareBasedPaymentsDetails Compensation Related Costs, Share Based Payments (Details) Details http://www.onegas.com/role/CompensationRelatedCostsShareBasedPaymentsTables 53 false false R54.htm 9955536 - Disclosure - EMPLOYEE BENEFIT PLANS (Details) Sheet http://www.onegas.com/role/EMPLOYEEBENEFITPLANSDetails EMPLOYEE BENEFIT PLANS (Details) Details http://www.onegas.com/role/EMPLOYEEBENEFITPLANSTables 54 false false R55.htm 9955537 - Disclosure - INCOME TAXES (Details) Sheet http://www.onegas.com/role/INCOMETAXESDetails INCOME TAXES (Details) Details http://www.onegas.com/role/INCOMETAXESNotes 55 false false R56.htm 9955538 - Disclosure - OTHER INCOME AND OTHER EXPENSE (Details) Sheet http://www.onegas.com/role/OTHERINCOMEANDOTHEREXPENSEDetails OTHER INCOME AND OTHER EXPENSE (Details) Details http://www.onegas.com/role/OTHERINCOMEANDOTHEREXPENSETables 56 false false R57.htm 9955539 - Disclosure - Property, Plant, and Equipment (Details) Sheet http://www.onegas.com/role/PropertyPlantandEquipmentDetails Property, Plant, and Equipment (Details) Details http://www.onegas.com/role/PropertyPlantandEquipmentTables 57 false false R58.htm 9955540 - Disclosure - COMMITMENTS AND CONTINGENCIES (Details) Sheet http://www.onegas.com/role/COMMITMENTSANDCONTINGENCIESDetails COMMITMENTS AND CONTINGENCIES (Details) Details http://www.onegas.com/role/COMMITMENTSANDCONTINGENCIESNotes 58 false false R59.htm 9955541 - Disclosure - DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Details) Note Sheet http://www.onegas.com/role/DERIVATIVEFINANCIALINSTRUMENTSANDFAIRVALUEMEASUREMENTSDetailsNote DERIVATIVE FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Details) Note Details http://www.onegas.com/role/DERIVATIVEFINANCIALINSTRUMENTSANDFAIRVALUEMEASUREMENTSTables 59 false false R60.htm 9955542 - Disclosure - VARIABLE INTEREST ENTITES (Details) Sheet http://www.onegas.com/role/VARIABLEINTERESTENTITESDetails VARIABLE INTEREST ENTITES (Details) Details http://www.onegas.com/role/VARIABLEINTERESTENTITESTables 60 false false All Reports Book All Reports ogs-20251231.htm ogs-20251231.xsd ogs-20251231_cal.xml ogs-20251231_def.xml ogs-20251231_lab.xml ogs-20251231_pre.xml ogs-20251231_g1.jpg http://fasb.org/us-gaap/2025 http://xbrl.sec.gov/cyd/2025 http://xbrl.sec.gov/dei/2025 http://xbrl.sec.gov/ecd/2025 true true