Exercise of ECP Warrants Proceeds from Warrant Exercises Extinguishment of Debt [Line Items] Extinguishment of Debt [Line Items] Supplemental cash flow information: Supplemental Cash Flow Information [Abstract] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Domain] Net income (loss) attributable to Summit Midstream Partners, LP Net income (loss) attributable to Summit Midstream Partners, LP Net Income (Loss) Attributable to Parent Noncurrent accrued environmental remediation Accrued Environmental Loss Contingencies, Noncurrent Consolidated Entities Consolidated Entities [Axis] Entity Emerging Growth Company Entity Emerging Growth Company Common units issued in exchange (in shares) Common Unit, Issued Common units issued for SMLP LTIP, net (in shares) Partners' Capital Account, Unit-based Payment Arrangement, Number of Units Statistical Measurement Statistical Measurement [Domain] Transaction costs Business Combination, Acquisition Related Costs Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Tax withholdings on Preferred Unit Exchange Partners' Capital, Decrease From Tax Withholding From Preferred Stock Exchange Partners' Capital, Decrease From Tax Withholding From Preferred Stock Exchange Increase (Decrease) In Equity Method Investments [Roll Forward] Increase (Decrease) In Equity Method Investments [Roll Forward] Increase (Decrease) In Equity Method Investments Natural gas, NGLs and condensate sales Oil and Condensate [Member] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Contract with Customer, Contract Asset, Contract Liability, and Receivable Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Marcellus Shale Marcellus Shale Segment [Member] Marcellus Shale segment. Entity Filer Category Entity Filer Category Other noncurrent assets Other Assets, Noncurrent Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Investment, Name Investment, Name [Axis] Segments Segments [Axis] Interest Rate Swaps Derivatives, Policy [Policy Text Block] Gain (loss) on ECP Warrants and other Gain (Loss) On ECP Warrants And Other Gain (Loss) On ECP Warrants And Other Units remaining available (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Net change in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Redemption price, expressed as percentage of principal amount Debt Instrument, Redemption Price, Percentage Gain (Loss) on Repurchase of Debt Instrument Gain (Loss) on Repurchase of Debt Instrument Net income (loss) Profit Loss Excluding Subsidiary Income Profit loss excluding subsidiary income. Gain on asset sales, net Gain on asset sales, net Gain (Loss) on Disposition of Assets Document Fiscal Year Focus Document Fiscal Year Focus Subsequent Event Type Subsequent Event Type [Domain] Common Units Limited Partner Common Units [Member] Limited partner common units. Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Debt issuance costs Payments of Financing Costs Long-lived asset impairments Impairment of Long-Lived Assets to be Disposed of Nonvested anti-dilutive phantom units excluded from the calculation of diluted EPU (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Contract with customer, liability, revenue recognized Contract with Customer, Liability, Revenue Recognized Subsequent Events [Abstract] Subsequent Events [Abstract] Land and line fill Landand Line Fill [Member] Land and line fill. Cash, Cash Equivalents and Restricted Cash Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block] Stock split, conversion ratio Stockholders' Equity Note, Stock Split, Conversion Ratio Grant date fair value (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 Commitment fee (as a percent) Line of Credit Facility, Commitment Fee Percentage Business Acquisition Business Acquisition [Axis] Net income (loss) attributable to limited partners Net income (loss) attributable to limited partners Net Income (Loss) Allocated to Limited Partners Loss contingency in period Loss Contingency, Loss in Period Purchase of common units in GP Buy-In Transaction Payments To Acquire Common Units Payments To Acquire Common Units Accrued interest Increase (Decrease) in Interest Payable, Net Principal Owner Principal Owner [Member] Award Type Award Type [Domain] Credit Facility Credit Facility [Domain] ASSETS Assets [Abstract] ECP Loan Repayment ECP Loan Repayment [Member] ECP Loan Repayment Segment Reconciling Items Segment Reconciling Items [Member] Restructuring costs Restructuring Costs Granted units (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Term Loan Credit Facility Term Loan Credit Facility [Member] Term loan credit facility. Entity Address, City or Town Entity Address, City or Town Interest in partnership per unit (in dollars per share) Shares Issued, Price Per Share Debt Instrument Debt Instrument [Axis] Utica Shale Utica Shale Segment [Member] Utica Shale segment. Summit Holdings And Finance Corporation Summit Holdings And Finance Corporation [Member] Summit Holdings and Finance Corporation. COMMITMENTS AND CONTINGENCIES Commitments and Contingencies Disclosure [Text Block] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Credit Agreement Credit Agreement [Member] Credit agreement. Related Party Related Party [Axis] Distributions from equity method investees September cash distributions Proceeds from Equity Method Investment, Distribution Accounts receivable Increase (Decrease) in Accounts Receivable Schedule of Accrued Environmental Remediation Schedule of Environmental Loss Contingencies by Site [Table Text Block] Capital expenditures in trade accounts payable (period-end accruals) Capital Expenditures Incurred but Not yet Paid Ratio of consolidated trailing 12-month EBITDA to net interest expense Ratio Of Consolidated Trailing12month E B I T D A To Net Interest Expense Ratio of consolidated trailing 12month EBITDA to net interest expense. SMP Holdings S M P Holdings [Member] SMP Holdings. Right-of-use assets relating to ASC Topic 842 Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Extinguishment of Debt [Axis] Extinguishment of Debt [Axis] Energy Capital Partners Energy Capital Partners [Member] Energy Capital Partners. Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Borrowings under Permian Transmission Credit Facility Permian Transmission Credit Facility: Permian Transmission's variable rate senior secured credit facility due March 8, 2028 Permian Transmission Credit Facility [Member] Permian transmission credit facility. Revolving Credit Facility: Summit Holdings' variable rate senior secured revolving credit facility due May 13, 2022 (1) Senior Notes Due May Twenty Twenty Two [Member] Senior notes due may twenty twenty two. Proceeds from issuance of Subsidiary Series A Preferred Units, net of issuance costs Proceeds from Issuance of Preferred Limited Partners Units Tender Offers of Senior Notes Tender Offers of Senior Notes Tender Offers of Senior Notes Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Entity Interactive Data Current Entity Interactive Data Current Unused portion under the facility Line of Credit Facility, Remaining Borrowing Capacity Maximum amount of debt outstanding for maturity to occur Debt Instrument, Covenant, Maximum Amount Outstanding For Maturity Debt Instrument, Covenant, Maximum Amount Outstanding For Maturity ECP Warrant exercise (in shares) Partners' Capital Account, Units, Issued For Warrant Exercises Partners' Capital Account, Units, Issued For Warrant Exercises REVENUE Revenue from Contract with Customer [Text Block] Unit-based compensation Partners' Capital Account, Unit-based Payment Arrangement, Amount Document Type Document Type Schedule of Disaggregated Revenue by Geographic Area and Major Products and Services Reportable Segments Disaggregation of Revenue [Table Text Block] Fair Value Measurement Fair Value Measurement [Domain] Unrealized loss on interest rate swaps Unrealized Gain (Loss) on Derivatives Entity Current Reporting Status Entity Current Reporting Status Preferred units, outstanding (in shares) Subsidiary Series A preferred unitholders, outstanding (in shares) Preferred Units, Outstanding Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Additions Contract With Customer Asset Additions Contract with customer asset, additions. Natural gas, NGLs and condensate sales Natural Gas N G L And Condensate Sales [Member] Natural gas, NGLs and condensate sales. 2019 Restructuring Activities Two Thousand Nineteen Restructuring Activities [Member] 2019 restructuring activities member Beginning October 15, 2024 Debt Instrument, Redemption, Period Two [Member] Plan Name Plan Name [Axis] Letters of credit Long-term Debt Change in Contract with Customer, Liability, Noncurrent [Roll Forward] Change in Contract with Customer, Liability, Noncurrent [Roll Forward] Change in Contract with Customer, Liability, Noncurrent Cash flows from investing activities: Net Cash Provided by (Used in) Investing Activities [Abstract] Document Transition Report Document Transition Report Beginning balance Ending balance Partners' Capital Interest cost capitalized Interest Paid, Capitalized, Investing Activities SMLP LTIP Long Term Incentive Plan [Member] Long-term incentive plan. Add: Reconciliation Of Net Income To E B I T D A Additions [Abstract] Reconciliation of net Income to EBITDA, additions. 2022 Senior Notes: Summit Holdings' 5.5% senior unsecured notes due August 15, 2022 (2) Five Point Five Percent Two Thousand Twenty Two Senior Notes [Member] 5.5% 2022 Senior Notes TOTAL LIABILITIES AND CAPITAL Liabilities and Equity Gathering and processing systems and related equipment Gas Gathering and Processing Equipment [Member] Deferred revenue Current deferred revenue, beginning balance Current deferred revenue, ending balance Contract with Customer, Liability, Current Scenario [Axis] Scenario [Axis] Restricted cash Restricted Cash Series A Preferred Unit Exchange Offer, net of shares withheld for taxes (in shares) Partners' Capital Account, Units, Converted Add: deemed contribution from Preferred Exchange Offer Deemed contribution to common unit holders Contributed Capital From Preferred Units Exchange Contributed Capital From Preferred Units Exchange Supplemental Cash Flow Elements [Abstract] Supplemental Cash Flow Elements [Abstract] Add: additions Contract With Customer Liability, Noncurrent, Additions Contract with customer liability noncurrent additions. Common limited partner capital (7,169,834 and 6,110,092 units issued and outstanding at September 30, 2021 and December 31, 2020, respectively) Limited Partners' Capital Account Concentration Risk [Line Items] Concentration Risk [Line Items] Common units not pledged as collateral (in shares) Common Units Not Pledged As Collateral Common units not pledged as collateral. LIABILITIES AND CAPITAL Liabilities and Equity [Abstract] Environmental Remediation Site Environmental Remediation Site [Axis] Interest Rate Swap Interest Rate Swap [Member] EARNINGS PER UNIT Earnings Per Share [Text Block] Percentage of ownership interest Equity Method Investment, Ownership Percentage Standby Letters of Credit Standby Letters of Credit [Member] Minimum Minimum [Member] Redemption amount Preferred Stock, Redemption Amount ORGANIZATION, BUSINESS OPERATIONS AND PRESENTATION AND CONSOLIDATION Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Reconciliation of Assets from Segment to Consolidated Reconciliation of Assets from Segment to Consolidated [Table Text Block] Other, net Increase (Decrease) in Other Operating Assets and Liabilities, Net Secured notes Long-term Line of Credit Common unit - diluted (in dollars per share) Net Income (Loss), Net of Tax, Per Outstanding Limited Partnership Unit, Diluted Common units issued prior to reverse unit split (in shares) Stock Issued During Period, Shares, Reverse Stock Splits Income (loss) before income taxes and equity method investment income Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Less unamortized debt issuance costs Deferred issuance costs Debt Issuance Costs, Net Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Proceeds from asset sale Proceeds from Sale of Productive Assets Subsidiary Subsidiaries Subsidiaries [Member] Barnett Shale Barnett Shale Segment [Member] Barnett Shale segment. Common units - basic (in shares) Weighted-average common units outstanding – basic (in shares) Weighted Average Limited Partnership Units Outstanding, Basic 2025 Senior Notes Two Thousand Twenty Five Senior Notes [Member] Two thousand twenty five senior notes. Trading Symbol Trading Symbol Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Table Text Block] Common limited partner capital (in shares), outstanding Common limited partner capital (in shares) Limited Partners' Capital Account, Units Outstanding Accrued compensation and employee benefits Accrued Employee Benefits, Current General and administrative General and Administrative Expense SUPPLEMENTAL CASH FLOW INFORMATION Cash Flow, Supplemental Disclosures [Text Block] Revision of Prior Period [Axis] Revision of Prior Period [Axis] Repurchase of senior notes Early Repayment of Senior Debt Restructuring Plan [Domain] Restructuring Plan [Domain] DEBT LIABILITY MANAGEMENT TRANSACTIONS Debt Disclosure [Text Block] Debt default amount Debt Instrument, Debt Default, Amount UNIT-BASED AND NONCASH COMPENSATION Share-based Payment Arrangement [Text Block] Warrant issuance for GP Buy-In Transaction Warrants Issued For Buy-In Transaction Warrants Issued For Buy-In Transaction Accounting Policies [Abstract] Accounting Policies [Abstract] Derivative Instrument Derivative Instrument [Axis] Partner Type of Partners' Capital Account, Name Partner Type of Partners' Capital Account, Name [Domain] Schedule Of Depreciation Expense And Capitalized Interest Costs Table Text Block Schedule Of Depreciation Expense And Capitalized Interest Costs Table [Table Text Block] Tabular disclosure of depreciation expense related to the property, plant and equipment and capitalized interest costs. Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] DJ Basin D J Basin Segment [Member] DJ Basin. Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Commitments and contingencies (Note 14) Commitments and Contingencies Subsequent Event [Table] Subsequent Event [Table] Adjustments related to capital reimbursement activity Adjustments Related To Capital Reimbursement Activity Adjustments related to capital reimbursement activity. Partner Capital Components Partner Capital Components [Domain] 2026 Notes 2026 Notes [Member] 2026 Notes Williston Basin Williston Basin Segment [Member] Williston Basin segment. Payments of Debt Issuance Costs Payments of Debt Issuance Costs Statement of Partners' Capital [Abstract] Statement of Partners' Capital [Abstract] Borrowings under ECP loans Proceeds from Issuance of Debt GP Buy-In Transaction assumption of noncontrolling interest in SMLP Partners Capital Account, Increase From Assumption of Noncontrolling Interest Partners Capital Account, Increase From Assumption of Noncontrolling Interest Document Period End Date Document Period End Date Effect of nonvested phantom units (in shares) Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements Total costs and expenses Costs and Expenses Class of Stock Class of Stock Class of Stock [Axis] Entity Registrant Name Entity Registrant Name Treasury stock (in shares) Treasury Stock, Shares Contract with Customer, Contract Asset, Contract Liability, and Receivable [Abstract] Contract with Customer, Contract Asset, Contract Liability, and Receivable [Abstract] Type of Cost, Good or Service [Extensible List] Cost, Product and Service [Extensible Enumeration] 2015 Blacktail Release 2015 Blacktail Release [Member] 2015 Blacktail Release Partners' Capital Partners Capital [Member] Partners capital. Subsidiary Series A Preferred Units (89,866 and 85,308 units issued and outstanding at September 30, 2021 and December 31, 2020, respectively) Temporary Equity, Carrying Amount, Attributable to Parent Number of common units purchased (in shares) Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Accrued expenses Accrued and unpaid liabilities Accrued Liabilities, Current Total revenues Revenue from Contract with Customer, Excluding Assessed Tax Ratio of total net indebtedness to consolidated trailing 12-month EBITDA Ratio Of Net Indebtedness To Consolidated Trailing12 Month E B I T D A Ratio of net indebtedness to consolidated trailing 12 month EBITDA. 2022 Senior Note Two Thousand Twenty Two Senior Notes [Member] Two thousand twenty two senior notes member. Equity [Abstract] Equity [Abstract] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Axis] Carrying Value Reported Value Measurement [Member] Consolidation Items Consolidation Items [Domain] Double E Double E Company L L C [Member] Double E company. Maximum period following end of quarter to distribute all available cash Distribution Of All Available Cash Maximum Period Following End Of Quarter Distribution of all available cash, maximum period following end of quarter. Variable Rate Variable Rate [Axis] Conversion of Preferred Units Partners' Capital Account, Exchanges and Conversions SEGMENT INFORMATION Segment Reporting Disclosure [Text Block] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Contract With Customer, Contract Asset, Contract Liability, and Receivable [Roll Forward] Contract With Customer, Contract Asset, Contract Liability, and Receivable [Roll Forward] Contract With Customer, Contract Asset, Contract Liability, and Receivable Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Abstract] Unit-based and noncash compensation Share-based Payment Arrangement, Noncash Expense RESTRUCTURING Restructuring and Related Activities Disclosure [Text Block] Variable Rate Variable Rate [Domain] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Depreciation expense Depreciation Repayment of ECP loans Repayments of Debt Long-term Debt, Type Long-term Debt, Type [Domain] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Effect of common unit issuances under SMLP LTIP Partners' Capital Account, Sale of Units Accrued expenses Increase (Decrease) in Accrued Liabilities Loss on ECP Warrants Gain (Loss) on Derivative Instruments, Net, Pretax Cash paid for taxes Income Taxes Paid Partners' leverage ratio Debt Instrument, Covenant, Leverage Ratio Debt Instrument, Covenant, Leverage Ratio 2020 Restructuring Activities Two Thousand Twenty Restructuring Activities [Member] 2020 restructuring activities member Environmental Remediation Site Environmental Remediation Site [Domain] Redemption percentage (as a percent) Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed Other, net Payments for (Proceeds from) Other Investing Activities Additional accruals Accrual for Environmental Loss Contingencies, Period Increase (Decrease) Capital expenditures Payments to Acquire Property, Plant, and Equipment Other current liabilities Other Liabilities, Current Net cash distributions to SMLP unitholders Partners' Capital Account, Distributions PARTNERS' CAPITAL AND MEZZANINE CAPITAL Partners' Capital Notes Disclosure [Text Block] Interest rate at period end Line of Credit Facility, Interest Rate at Period End Maximum Maximum [Member] Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement [Abstract] Loss Contingency, Nature [Domain] Loss Contingency, Nature [Domain] Total liabilities Liabilities Legal Entity Legal Entity [Axis] Total cash consideration paid for extinguishment Total cash consideration paid for extinguishment Payment for Debt Extinguishment or Debt Prepayment Cost Award Type Award Type [Axis] Debt Tender Offers Debt Tender Offers [Member] Debt Tender Offers Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Consolidation Items Consolidation Items [Axis] EQUITY METHOD INVESTMENTS Equity Method Investments and Joint Ventures Disclosure [Text Block] Schedule of Cash Flow, Supplemental Disclosures Schedule of Cash Flow, Supplemental Disclosures [Table Text Block] Partner Capital Components Partner Capital Components [Axis] Repurchase of Senior Notes Repayments of Senior Debt Gain on early extinguishment of debt Gain on extinguishment of debt Gain on early extinguishment of debt Gain (Loss) on Extinguishment of Debt 2025 Senior Notes: Summit Holdings' 5.75% senior unsecured notes due April 15, 2025 Five Point Seven Five Percent Two Thousand Twenty Five Senior Notes [Member] 5.75% 2022 Senior Notes. Noncash investing and financing activities: Noncash Investing and Financing Items [Abstract] Accrued and unpaid distributions Accrued and Unpaid Distributions Accrued and Unpaid Distributions Redemption accretion Accretion of Subsidiary Series A Preferred Units Preferred Stock, Accretion of Redemption Discount Debt offering Debt Instrument, Face Amount Interest expense Interest expense Interest Expense Interest rate during period (as a percent) Debt Instrument, Interest Rate, Effective Percentage Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] City Area Code City Area Code Basis difference Equity Method Investment Amortizationof Difference Between Carrying Amountand Underlying Equity Equity method investment, amortization of difference between carrying amount and underlying equity. Reportable Segments Operating Segments [Member] Litigation Case [Domain] Litigation Case [Domain] Ad valorem taxes payable Accrual for Taxes Other than Income Taxes, Current Commitment fee on unused portion of the facility (as a percent) Line of Credit Facility, Unused Capacity, Commitment Fee Percentage Revision of Prior Period [Domain] Revision of Prior Period [Domain] Equity Method Investments Equity Method Investments [Table Text Block] Reconciliation of Revenue from Segments to Consolidated Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Condensed Financial Statements [Table] Condensed Financial Statements [Table] Income Statement [Abstract] Income Statement [Abstract] Investment in equity method investees Ending balance Beginning balance Equity method investment Equity Method Investments Amendment Flag Amendment Flag Concentration Risk [Table] Concentration Risk [Table] Partners Capital [Table] Partners Capital [Table] Partners' capital. Revolving credit facility Secured Long-term Debt, Noncurrent Fair Value Estimate of Fair Value Measurement [Member] Partner Type Partner Type [Axis] Repayments on Revolving Credit Facility Repayments of Lines of Credit Senior notes Notes Payable, Fair Value Disclosure Income tax benefit (expense) Income Tax Expense (Benefit) Accounts receivable, net Accounts Receivable, after Allowance for Credit Loss, Current Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Total current assets Assets, Current Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Adjusted EBITDA Total of reportable segments' measures of profit Adjusted Earnings Before Interest Taxes Depreciation And Amortization Adjusted earnings before interest, taxes, depreciation, and amortization. Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Fair value, other assets Other Assets, Fair Value Disclosure Entity File Number Entity File Number Equity Method Investments and Joint Ventures [Abstract] Equity Method Investments and Joint Ventures [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Accrued environmental remediation Accrued Environmental Loss Contingencies, Current Product and Service [Axis] Product and Service [Axis] Long-Lived Tangible Asset Long-Lived Tangible Asset [Domain] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Grant date fair value (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value Entity Small Business Entity Small Business Restructuring Plan [Axis] Restructuring Plan [Axis] Schedule of Extinguishment of Debt Schedule of Extinguishment of Debt [Table Text Block] Partners Capital [Line Items] Partners Capital [Line Items] Partners' capital. GP Buy-In GP Buy-In [Member] GP Buy-In Secured Notes Indenture, 2026 Secured Notes Indenture, 2026 [Member] Secured Notes Indenture, 2026 Beginning October 15, 2025 Debt Instrument, Redemption, Period Three [Member] Issued units (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period Increase (Decrease) in Partners' Capital [Roll Forward] Increase (Decrease) in Partners' Capital [Roll Forward] Extinguishment of Debt, Type [Domain] Extinguishment of Debt, Type [Domain] Schedule of Equity Method Investments [Table] Schedule of Equity Method Investments [Table] SMLP common units pledged as collateral under the SMPH Term Loan (in shares) Common Units Pledged As Collateral Common units pledged as collateral. Statement [Line Items] Statement [Line Items] Litigation Case [Axis] Litigation Case [Axis] Limited Partners' Capital Account, Class Limited Partners' Capital Account, Class [Domain] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Deferred revenue, net Increase (Decrease) in Contract with Customer, Liability Ohio Gathering Ohio Gathering Segment [Member] Ohio Gathering segment. 2025 Senior Notes Senior Notes Due2025 [Member] Senior Notes due 2025 Revenue, remaining performance obligation, amount Revenue, Remaining Performance Obligation, Amount Damages Payable To State Governments Over Six Years Damages Payable To State Governments Over Six Years [Member] Damages Payable To State Governments Over Six Years Schedule of Carrying Values and Estimated Fair Values of Debt Instruments Schedule of Carrying Values and Estimated Fair Values of Debt Instruments [Table Text Block] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Common Units Common Units [Member] Common unit. Entity Address, State or Province Entity Address, State or Province Estimated fair value (Level 2) Fair Value, Inputs, Level 2 [Member] Other Other Capitalized Property Plant and Equipment [Member] PIK distributions Dividends, Preferred Stock, Paid-in-kind Long-Lived Tangible Asset Long-Lived Tangible Asset [Axis] DEFERRED REVENUE Contract With Customer Liability Disclosure [Text Block] Contract with customer liability disclosure. Noncurrent deferred revenue Noncurrent deferred revenue, beginning balance Noncurrent deferred revenue, ending balance Contract with Customer, Liability, Noncurrent Total partners' capital Beginning balance Ending balance Partners' Capital, Including Portion Attributable to Noncontrolling Interest Corporate and Other Corporate, Non-Segment [Member] Segment Reporting [Abstract] Segment Reporting [Abstract] Unsecured notes Unsecured Long-term Debt, Noncurrent Entity Entity [Domain] Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Mezzanine Capital Temporary Equity [Abstract] Use of Estimates Use of Estimates, Policy [Policy Text Block] Trade accounts payable Increase (Decrease) in Accounts Payable, Trade Schedule of Earnings Per Share, Basic and Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Entity Shell Company Entity Shell Company Local Phone Number Local Phone Number Forecast Forecast [Member] Common units - diluted (in shares) Weighted-average common units outstanding – diluted (in shares) Weighted Average Limited Partnership Units Outstanding, Diluted TOTAL ASSETS Assets Assets Ownership percentage of principal Debt Instrument, Covenant, Ownership Percentage of Principal Debt Instrument, Covenant, Ownership Percentage of Principal Investment, Name Investment, Name [Domain] Plan Name Plan Name [Domain] Net cash distributions to noncontrolling interest SMLP unitholders Payments to Noncontrolling Interests Cash interest paid Interest Paid, Excluding Capitalized Interest, Operating Activities Piceance Basin Piceance Basin Segment [Member] Piceance Basin segment. Repayments on SMPH Term Loan Repayments of Secured Debt Common Noncontrolling Interest Common Noncontrolling Interests [Member] Common noncontrolling interests. Other Partners' Capital, Other Noncontrolling Interest Noncontrolling Interest [Member] Product and Service Product and Service [Domain] Stated interest rate (as a percent) Debt Instrument, Interest Rate, Stated Percentage Derivative Contract Derivative Contract [Domain] Interest coverage ratio Debt Instrument, Covenant, Interest Coverage Ratio Debt Instrument, Covenant, Interest Coverage Ratio Net loss attributable to noncontrolling interest Net Income (Loss) Attributable to Noncontrolling Interest ABL Revolver ABL Revolver [Member] ABL Revolver Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Revolving credit facility Revolving Credit Facility [Member] SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES AND RECENTLY ISSUED ACCOUNTING STANDARDS APPLICABLE TO THE PARTNERSHIP Significant Accounting Policies [Text Block] Revenue, remaining performance obligation, expected timing of satisfaction Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Adjustments related to MVC shortfall payments Adjustments Related To Minimum Volume Commitments Shortfall Payments Adjustments related to minimum volume commitments shortfall payments. Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Subsidiary Series A preferred unitholders, issued (in shares) Preferred units issued (in shares) Preferred Units, Issued Derivative liability, notional amount Derivative Liability, Notional Amount Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Entity Tax Identification Number Entity Tax Identification Number Subsequent Event [Line Items] Subsequent Event [Line Items] Segments Segments [Domain] OGC Ohio Gathering Company L L C [Member] Ohio Gathering Company, L.L.C. Noncash lease expense Operating Lease, Right-of-Use Asset, Amortization Expense Schedule Of Partner Units Activity Schedule Of Partner Units Activity Table [Table Text Block] Schedule of partner units activity. SUBSEQUENT EVENTS Subsequent Events [Text Block] Unused portion of the Permian Transmission Credit facility Debt Instrument, Unused Borrowing Capacity, Amount Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Receivables with customers Unbilled Contracts Receivable Revenue From Contract With Customer [Table] Revenue From Contract With Customer [Table] Revenue from contract with customer. Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Weighted-average limited partner units outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Vesting period Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Net income (loss) per limited partner unit: Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax [Abstract] Income from equity method investees Income from equity method investees Income (Loss) from Equity Method Investments Business Acquisition, Acquiree Business Acquisition, Acquiree [Domain] FINANCIAL INSTRUMENTS Fair Value Disclosures [Text Block] Depreciation and amortization Depreciation Depletion And Amortization Including Amortization Of Above And Below Market Leases Depreciation depletion and amortization including amortization of above and below market leases. Trade accounts payable Accounts Payable, Current Depreciation and amortization Depreciation, Depletion and Amortization Borrowings under Credit Facilities Proceeds from Long-term Lines of Credit Summit Investments Summit Investments [Member] Summit investments. Contract assets, beginning of period Contract assets, end of period Contract assets included in accounts receivable Contract with Customer, Asset, after Allowance for Credit Loss Organization And Business Operations [Line Items] Organization And Business Operations [Line Items] Organization and business operations. Other income (expense), net Other Operating Income (Expense), Net Series A Preferred Units Series A Preferred Units [Member] Series A preferred units. Expected payment Accrual for Environmental Loss Contingencies, Expected Payment Accrual for Environmental Loss Contingencies, Expected Payment Cost of natural gas and NGLs Cost of Goods and Services Sold Revenues: Revenues [Abstract] Meadowlark Midstream Gathering System Meadowlark Midstream Gathering System [Member] Meadowlark Midstream gathering system. Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Schedule of Estimated Revenue Expected to be Recognized and MVC Shortfall Payments Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Other revenues Product and Service, Other [Member] Consolidated Entities Consolidated Entities [Domain] Unpaid penalties and fines, fixed rate (as a percent) Accrual for Environmental Loss Contingencies, Discount Rate Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Capitalized interest Capitalized Interest Costs, Including Allowance for Funds Used During Construction Reconciliation Of Net Income To Adjusted EBITDA Reconciliation Of Net Income To Adjusted E B I T D A Table [Table Text Block] Reconciliation of net income to adjusted EBITDA. Payments made Accrual for Environmental Loss Contingencies, Payments Change in Contract with Customer, Liability, Current [Roll Forward] Change in Contract with Customer, Liability, Current [Roll Forward] Change in Contract with Customer, Liability, Current Loss Contingencies [Line Items] Loss Contingencies [Line Items] Condensed Financial Statements, Captions [Line Items] Condensed Financial Statements, Captions [Line Items] Property, plant and equipment, net Property, plant and equipment, net Property, Plant and Equipment, Net PROPERTY, PLANT, AND EQUIPMENT Property, Plant and Equipment Disclosure [Text Block] Redemption covenant, percent of initial principal amount remaining outstanding Debt Instrument, Covenant, Redemption, Percent of Initial Principal Amount Remaining Outstanding Debt Instrument, Covenant, Redemption, Percent of Initial Principal Amount Remaining Outstanding Subsidiary Series A Preferred Units Subsidiary Series A Preferred Units [Member] Subsidiary Series A Preferred Units Other noncurrent liabilities Other Liabilities, Noncurrent Schedule of Debt Schedule of Long-term Debt Instruments [Table Text Block] Debt Instrument [Line Items] Debt Instrument [Line Items] Permian Basin Permian Basin Segment [Member] Permian Basin segment member. Earnings Per Share [Abstract] Earnings Per Share [Abstract] Total Property, Plant and Equipment, Gross Document Quarterly Report Document Quarterly Report Borrowing capacity Line of Credit Facility, Current Borrowing Capacity Operation and maintenance Utilities Operating Expense, Maintenance and Operations Line of Credit Facility [Table] Line of Credit Facility [Table] Loss contingency accrual Loss Contingency Accrual Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Costs and expenses: Costs and Expenses [Abstract] Long-term debt Long-term Debt, Excluding Current Maturities Organization And Business Operations [Table] Organization And Business Operations [Table] Disclosure pertaining to organization and business operations. Schedule of Equity Method Investments [Line Items] Schedule of Equity Method Investments [Line Items] Accrual for Environmental Loss Contingencies [Roll Forward] Accrual for Environmental Loss Contingencies [Roll Forward] Document Fiscal Period Focus Document Fiscal Period Focus Open Market Repurchases Open Market Repurchases [Member] Open Market Repurchases Series A Preferred Units Series A Preferred Stock Series A Preferred Stock [Member] Net income (loss) Net income (loss) Net income (loss) Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Amortization of debt issuance costs Amortization of Debt Issuance Costs Proportional adjusted EBITDA for equity method investees Adjusted Earnings Before Interest Taxes Depreciation And Amortization Proportional Equity Method Investment Adjustment Adjusted earnings before interest, taxes, depreciation, and amortization, proportional equity method investment adjustment. Construction in progress Construction in Progress [Member] Tax withholdings and associated payments on vested SMLP LTIP awards Partners Capital Account Tax Withholding For Unit Based Compensation Partners' capital account tax withholding for unit-based compensation. Cash, cash equivalents and restricted cash, beginning of period Cash, cash equivalents and restricted cash, end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents ABL Facility ABL Facility [Member] ABL Facility Revenue From Contract With Customer [Line Items] Revenue From Contract With Customer [Line Items] Revenue from contract with customer. Limited Partners' Capital Account by Class Limited Partners' Capital Account by Class [Axis] Debt discharge and restructuring Consideration For Consensual Debt Discharge And Restructuring Consideration for a consensual debt discharge and restructuring. Other, net Proceeds from (Payments for) Other Financing Activities Beginning October 15, 2023 Debt Instrument, Redemption, Period One [Member] Schedule of Extinguishment of Debt [Table] Schedule of Extinguishment of Debt [Table] Entity Central Index Key Entity Central Index Key Units, beginning balance (in shares) Units, ending balance (in shares) Partners' Capital Account, Units Common limited partner capital (in shares), issued Limited Partners' Capital Account, Units Issued LIBOR London Interbank Offered Rate (LIBOR) [Member] Security Exchange Name Security Exchange Name Summit Midstream Partners Holdings L L C Summit Midstream Partners Holdings L L C [Member] Summit Midstream Partners Holdings, LLC. Accrued interest Interest Payable, Current Long-term Debt, Type Long-term Debt, Type [Axis] Related Party Related Party [Domain] Current Fiscal Year End Date Current Fiscal Year End Date Applicable margin (as a percent) Debt Instrument, Basis Spread on Variable Rate Add: additions Contract With Customer Liability, Current, Additions Contract with customer liability current additions. Damages Payable To Federal Government over Five Years Damages Payable To Federal Government over Five Years [Member] Damages Payable To Federal Government over Five Years Measurement Basis Measurement Basis [Axis] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Accrued environmental remediation, net Increase (Decrease) in Regulatory Liabilities Investment in Double E equity method investee Investment in equity method investment Payments to Acquire Equity Method Investments Class of Stock [Line Items] Class of Stock [Line Items] Credit Facility Credit Facility [Axis] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Less: accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Series A Preferred Units (143,447 and 162,109 units issued and outstanding at September 30, 2021 and December 31, 2020, respectively) Preferred Units, Preferred Partners' Capital Accounts Corporate and Other expense Corporate And Other Expenses Corporate and other expenses. Gathering services and related fees Gathering Services And Related Fees [Member] Gathering services and related fees. Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities [Abstract] Less: revenue recognized Contract With Customer Liability, Current, Revenue Recognized Contract with customer liability current revenue recognized. Consolidation Consolidation, Policy [Policy Text Block] Schedule of Information about Contract Assets from Contracts with Customers Schedule Of Contract With Customer Asset Table [Table Text Block] Schedule of contract with customer, asset. Total current liabilities Liabilities, Current Class of Stock Class of Stock [Domain] Cash paid to acquire investment Payments to Acquire Businesses, Gross Debt issued as a percent of face value Debt Instrument, Issued As A Percentage of Face Value Debt Instrument, Issued As A Percentage of Face Value Borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Loss Contingencies [Table] Loss Contingencies [Table] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Common unit - basic (in dollars per share) Net Income (Loss), Per Outstanding Limited Partnership Unit, Basic, Net of Tax Entity Address, Postal Zip Code Entity Address, Postal Zip Code Proceeds from asset sale Proceeds From Sale Of Assets Proceeds from sale of assets. Transfers out Contract with Customer, Asset, Reclassified to Receivable ECP Holdings Warrant E C P Holdings Warrant [Member] ECP holdings warrant. Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Debt Instrument, Name Debt Instrument, Name [Domain] Title of 12(b) Security Title of 12(b) Security Statement [Table] Statement [Table] Other current assets Other Assets, Current Accrued environmental remediation, beginning balance Accrued environmental remediation, ending balance Accrual for Environmental Loss Contingencies Partners' Capital Partners' Capital [Abstract] New accounting standards recently implemented New Accounting Pronouncements, Policy [Policy Text Block] Debt Instrument, Redemption, Period Debt Instrument, Redemption, Period [Domain] Statistical Measurement Statistical Measurement [Axis] Subsequent Event Subsequent Event [Member] Cover [Abstract] Cover [Abstract] Working Capital Credit Facility Working Capital Credit Facility [Member] Working Capital Credit Facility. Intangible assets, net Finite-Lived Intangible Assets, Net Number of directors Number Of Directors Number of directors. Extinguishment of debt, amount Extinguishment of Debt, Amount Gathering services and related fees Natural Gas, Gathering, Transportation, Marketing and Processing [Member] 2022 Senior Notes Senior Notes Due2022 [Member] Senior Notes due 2022. Ad valorem taxes payable Increase (Decrease) in Property and Other Taxes Payable Repurchase of common units under GP Buy-In Transaction Partners Capital Account, Decrease From Repurchase of Common Units Partners Capital Account, Decrease From Repurchase of Common Units Less: reclassification to current deferred revenue Contract With Customer Liability, Noncurrent, Reclassification To Current Contract with customer liability noncurrent reclassification to current. Natural Resource Damages To Federal and State Governments Natural Resource Damages To Federal and State Governments [Member] Natural Resource Damages To Federal and State Governments Ratio of first lien net indebtedness to consolidated trailing 12-month EBITDA Ratio Of First Lien Net Indebtedness To Consolidated Trailing12 Month E B I T D A Ratio of first lien net indebtedness to consolidated trailing 12 month EBITDA. Scenario [Domain] Scenario [Domain] Adjustments to reconcile net income (loss) to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Subsequent Event Type Subsequent Event Type [Axis] Phantom Units Phantom Share Units (PSUs) [Member] Debt Instrument, Redemption, Period Debt Instrument, Redemption, Period [Axis] Legal fines and other fees Accrual for Environmental Loss Contingencies, Charges to Expense for New Losses Penalties and fines, payment period Environmental Loss Contingencies, Penalties and Fines, Payment Period Environmental Loss Contingencies, Penalties and Fines, Payment Period Increase in loss contingency accrual Loss Contingency Accrual, Period Increase (Decrease) Deferred Revenue Disclosure [Abstract] Deferred Revenue Disclosure [Abstract] Natural Gas Liquids [Member]