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Related Party Transaction [Table] Schedule of Equity Method Investments [Table] Equity Method Investment [Table] Specific review of probable future collections based on receivable balances, threshold duration Specific Review Of Probable Future Collections Based On Receivable Balances, Threshold Duration Specific Review Of Probable Future Collections Based On Receivable Balances, Threshold Duration Other current assets Other Assets, Current Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Other (Income) and Deductions Other Nonoperating Income (Expense) [Abstract] All Trading Arrangements All Trading Arrangements [Member] Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Operating Income Operating Income (Loss) Schedule of Cash Dividends Declared Dividends Declared [Table Text Block] Remaining performance obligation Revenue, Remaining Performance 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Contract with Customer, Basis of Pricing [Axis] Contract with Customer, Basis of Pricing [Axis] Revolving Credit Facility, expiring October 2029 Revolving Credit Facility, Expiring October 2029 [Member] Revolving Credit Facility, Expiring October 2029 Equity Components [Axis] Equity Components [Axis] Operation and maintenance Other Cost and Expense, Operating Accounts receivable, net Increase (Decrease) in Accounts Receivable Related Party Related Party [Member] Capitalized costs to obtain or fulfill contracts Capitalized Contract Cost, Net Income taxes, net of refunds received Income Tax Paid, after Refund Received South Romeo VIE Variable Interest Entity, Primary Beneficiary, South Romeo Gas Storage Corporation [Member] Variable Interest Entity, Primary Beneficiary, South Romeo Gas Storage Corporation Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Less: Net Income Attributable to Noncontrolling 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Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Equity method investment, non-consolidated investees Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] Equity Awards Adjustments Equity Awards Adjustments [Member] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Past due Financial Asset, Past Due [Member] Total Liabilities and Equity Liabilities and Equity 2032 Notes 2032 Senior Notes [Member] 2032 Senior Notes Employee Stock Option Share-Based Payment Arrangement, Option [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Noncontrolling interests Equity, Attributable to Noncontrolling Interest Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Related Party [Domain] Related and Nonrelated Parties [Domain] Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Other income Other Nonoperating Income (Expense) Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Property Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization [Abstract] Temporary step up maximum consolidated net leverage ratio Debt Instrument, Covenant, Consolidated Net Leverage Ratio, Temporary Step-Up Maximum Debt Instrument, Covenant, Consolidated Net Leverage Ratio, Temporary Step-Up Maximum Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock ($0.01 par value, 50,000,000 shares authorized, and no shares issued or outstanding as of June 30, 2026 and December 31, 2025) Preferred Stock, Value, Issued Adjustment to Compensation: Adjustment to Compensation [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest, net of interest capitalized Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Deferred property taxes Prepaid Taxes Consideration value related to consummation or acquisition or investment required to temporarily step up maximum consolidated net leverage ratio Debt Instrument, Covenant, Acquisition Consideration Value Triggering Temporary Step-Up In Maximum Consolidated Net Leverage Ratio Debt Instrument, Covenant, Acquisition Consideration Value Triggering Temporary Step-Up In Maximum Consolidated Net Leverage Ratio Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount REGULATORY MATTERS Schedule of Regulatory Assets and Liabilities [Text Block] Name Measure Name INCOME TAXES Income Tax Disclosure [Text Block] Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Additional Paid-In Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Financing Receivables Financing Receivable [Policy Text Block] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Name Trading Arrangement, Individual Name Cash and cash equivalents Cash Cash and Cash Equivalent VIE ownership percentage Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage Company Selected Measure Amount Company Selected Measure Amount Financial Asset, Period Past Due [Axis] Financial Asset, Aging [Axis] Dividends from equity method investees Proceeds from Equity Method Investment, Distribution Stock-based compensation (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Net Income Net Income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Current Assets Assets, Current [Abstract] Non-PEO NEO Non-PEO NEO [Member] Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Cash paid for: Cash Paid For (Received From) Supplemental Cash Flow Information [Abstract] Cash Paid For Supplemental Cash Flow Information Income Tax Expense Income Tax Expense (Benefit) Other Assets Regulated Entity, Other Assets, Noncurrent [Abstract] Award Timing Method Award Timing Method [Text Block] Net Increase in Cash and Cash Equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] VIE Variable interest entity, primary beneficiary Variable Interest Entity, Primary Beneficiary [Member] NEW ACCOUNTING PRONOUNCEMENTS Accounting Standards Update and Change in Accounting Principle [Text Block] Net Income Attributable to DT Midstream Net Income Attributable to DT Midstream Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Restatement Determination Date: Restatement Determination Date [Axis] Revenue Expected to be Recognized in Future Periods Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Interest income Investment Income, Interest Summary of Contact Liability Activity Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] 2029 Notes 2029 Senior Notes [Member] 2029 Senior Notes Revenues Revenues [Abstract] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]