1001 - Document - Cover link:presentationLink link:definitionLink link:calculationLink 1002 - Statement - Statements of Net Assets Available for Benefits link:presentationLink link:definitionLink link:calculationLink 1003 - Statement - Statement of Changes in Net Assets Available for Benefits link:presentationLink link:definitionLink link:calculationLink 1004 - Disclosure - Description of Plan link:presentationLink link:definitionLink link:calculationLink 1005 - Disclosure - Summary of Accounting Policies link:presentationLink link:definitionLink link:calculationLink 1006 - Disclosure - Investments link:presentationLink link:definitionLink link:calculationLink 1007 - Disclosure - Income Taxes link:presentationLink link:definitionLink link:calculationLink 1008 - Disclosure - Party-In-Interest And Related Party Transactions link:presentationLink link:definitionLink link:calculationLink 1009 - Disclosure - Subsequent Events link:presentationLink link:definitionLink link:calculationLink 1010 - Disclosure - Schedule H, Part IV, Line 4i – Schedule Of Assets (Held At End Of Year) link:presentationLink link:definitionLink link:calculationLink 1011 - Disclosure - Summary of Accounting Policies (Policies) link:presentationLink link:definitionLink link:calculationLink 1012 - Disclosure - Investments (Tables) link:presentationLink link:definitionLink link:calculationLink 1013 - Disclosure - Description of Plan - Additional Informaton (Detail) link:presentationLink link:definitionLink link:calculationLink 1014 - Disclosure - Investments - Schedule on Plan's Investment Assets At Fair Value (Detail) link:presentationLink link:definitionLink link:calculationLink 1015 - Disclosure - Income Taxes - Additional Information (Detail) link:presentationLink link:definitionLink link:calculationLink 1016 - Disclosure - Party-In-Interest And Related Party Transactions - Additional Information (Detail) link:presentationLink link:definitionLink link:calculationLink 1017 - Disclosure - Schedule H, Part Iv, Line 4i - Schedule Of Assets (Held At End Of Year) (Detail) link:presentationLink link:definitionLink link:calculationLink 1018 - Disclosure - Schedule H, Part Iv, Line 4i - Schedule Of Assets (Held At End Of Year) (Detail) Alternate link:presentationLink link:definitionLink link:calculationLink 1019 - Statement - Statement of Changes in Net Assets Available for Benefits Alternate 1 link:presentationLink link:definitionLink link:calculationLink Cover [Abstract] Document Information [Table] Legal Entity [Axis] Entity [Domain] EBP 001 [Member] Document Information [Line Items] Document Type Amendment Flag Document Period End Date Document Fiscal Year Focus Document Fiscal Period Focus Entity Registrant Name Entity Central Index Key Current Fiscal Year End Date EBP, Statement of Net Asset Available for Benefit [Abstract] EBP, Statement of Net Asset Available for Benefit [Table] EBP, Statement of Net Asset Available for Benefit [Line Items] EBP, Asset [Abstract] Assets EBP, Investment, Excluding Plan Interest in Master Trust, Fair Value Investments at fair value (Note 3) EBP, Investment, excluding plan interest in master trust, fair value EBP, Employer Contribution, Receivable Employer contributions receivable EBP, Asset Held for Investment, Participant Loan, after Deemed Distribution Notes receivable from participants EBP, Net Asset Available for Benefit Net Assets Available for Benefits Beginning of year End of year EBP, Statement of Change in Net Asset Available for Benefit [Abstract] EBP, Statement of Change in Net Asset Available for Benefit [Table] EBP, Statement of Change in Net Asset Available for Benefit [Line Items] EBP, Change in Net Asset Available for Benefit, Increase [Abstract] Additions EBP, Change in Net Asset Available for Benefit, Increase from Contribution [Abstract] Contributions EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Excluding Rollover Employee contributions EBP, Change in Net Asset Available for Benefit, Increase from Employer Contribution, Cash and Noncash Employer contributions EBP, Change in Net Asset Available for Benefit, Increase from Participant Contribution, Rollover Rollovers EBP, Change in Net Asset Available for Benefit, Increase from Contribution Total Contributions EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Investment Income (Loss), after Investment Expense [Abstract] Investment Income EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Gain (Loss) on Investment Net appreciation in fair value of investments EBP, Change in Net Asset Available for Benefit, Increase from Interest and Dividend Income on Investment Interest and dividend income EBP, Change in Net Asset Available for Benefit, Increase (Decrease) from Income (Loss) on Investment Total Investment Income EBP, Change in Net Asset Available for Benefit, Increase Total Additions EBP, Change in Net Asset Available for Benefit, Decrease [Abstract] Deductions EBP, Change in Net Asset Available for Benefit, Decrease from Payment to Participant Benefits paid to participants EBP, Change in Net Asset Available for Benefit, Decrease from Administrative Expense Administrative expenses EBP, Change in Net Asset Available for Benefit, Decrease Total Deductions EBP, Change in Net Asset Available for Benefit, Increase (Decrease) Net Increase in Net Assets Available for Benefits EBP, Net Asset Available for Benefit [Abstract] Net Assets Available for Benefits EBP, Accounting Policy, Accounting Standard Update, and Change in Accounting Principle [Abstract] EBP, Accounting Policy [Table] EBP, Accounting Policy [Line Items] Employee benefit plan enhanced contribution EBP, Description of Plan [Text Block] Description of plan EBP, Summary of Accounting Policy [Text Block] Summary of accounting policies EBP, Investment, Fair Value and NAV [Abstract] EBP, Investment, Fair Value and NAV [Table] EBP, Investment, Fair Value and NAV [Line Items] EBP, Investment, Fair Value and NAV [Text Block] Investments EBP, Tax Status [Abstract] EBP, Tax Status [Table] EBP, Tax Status [Line Items] EBP, Tax Status [Text Block] Income taxes EBP, Related Party and Party-in-Interest Transactions [Abstract] EBP, Related Party and Party-in-Interest Transactions [Table] EBP, Related Party and Party-in-Interest Transactions [Line Items] EBP, Related Party and Party-in-Interest Transactions [Text Block] Party-in-interest and related party transactions EBP, Subsequent Event [Abstract] EBP, Subsequent Event [Table] EBP, Subsequent Event [Line Items] EBP, Subsequent Event [Text Block] Subsequent events EBP, Schedule of Asset Held for Investment [Abstract] EBP, Schedule of Asset Held for Investment [Table] EBP, Schedule of Asset Held for Investment [Line Items] EBP, Schedule of Asset Held for Investment [Table Text Block] Schedule of Assets (Held at End of Year) EBP, Basis of Accounting [Policy Text Block] Basis of Accounting EBP, Use of Estimate [Policy Text Block] Use of Estimates EBP, Investment [Policy Text Block] Investment Valuation and Income Recognition EBP, Note Receivable from Participant [Policy Text Block] Notes Receivable from Participants EBP, Contribution [Policy Text Block] Contributions EBP, Payment to Participant [Policy Text Block] Payment of Benefits EBP, Investment, Fair Value and NAV [Table Text Block] Schedule on Plan's investment assets at fair value EBP, Participant Contribution, Pretax, Maximum Annual Compensation to Total Compensation, Percentage EBP, Participant contribution, pretax, maximum annual compensation to total compensation, percentage Employee Benefit Plan Participant Contribution After Tax Maximum Annual Compensation To Total Compensation Percentage Employee benefit plan participant contribution after tax maximum annual compensation to total compensation percentage Employee benefit plan participant contribution after tax maximum annual compensation to total compensation percentage. EBP, Participant Contribution, Automatic, Deferral Rate EBP, Participant contribution, automatic, deferral rate EBP, Employer Contribution, Matching Percentage EBP, Employer contribution, matching percentage EBP, Employer Contribution, Participant Compensation Matched, Percentage EBP, Employer contribution, participant compensation matched, percentage Employee Benefit Plan Enhanced Contribution Employee benefit plan enhanced contribution Employee benefit plan enhanced contribution EBP, Note Receivable from Participant, Account, Minimum Borrowing, Amount EBP, Note receivable from participant, account, minimum borrowing, amount EBP, Note Receivable from Participant, Account, Maximum Borrowing, Amount EBP, Note receivable from participant, account, maximum borrowing, amount EBP Employer Contribution Vesting Period Of Service EBP Employer contribution vesting period of service EBP Employer contribution vesting period of service EBP Participant Contribution Vesting Percentage EBP Participant contribution vesting percentage EBP Participant contribution vesting percentage Emp Interest Rates On Note Outstanding EMP Interest rates on note outstanding Emp interest rates on note outstanding EBP Employer Contribution Vesting Period Percentage EBP Employer contribution vesting period percentage EBP Employer contribution vesting period percentage EBP, Forfeited Nonvested Account EBP, Forfeited nonvested account Statistical Measurement [Axis] Statistical Measurement [Domain] Maximum [Member] Minimum [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 [Member] Fair Value, Inputs, Level 3 [Member] Fair Value Measured at Net Asset Value Per Share [Member] Other Investment Type [Axis] Investments [Domain] Mutual Fund [Member] Common Collective Trust [Member] South Bow Common Stock [Member] TC Energy Common Stock [Member] EBP, Tax Determination Letter, Date EBP, Tax Determination Letter, Date EBP, Investment, Number of Shares EBP, Investment, number of Shares Employee Benefit Plan Investment Number Of Value Purchased Stock Employee benefit plan investment number of value purchased stock Employee Benefit Plan Investment Number Of Value Purchased Stock. EBP, Investment, Purchased, Number of Shares EBP, Investment, purchased, number of shares EBP, Investment, Sold, Number of Shares EBP, Investment, sold, number of shares Emplyee Benefit Plan Dividend Income On Investment Employee benefit plan dividend income on investment Emplyee benefit plan dividend income on investment. Bow Common Stock [Member] Energy Common Stock [Member] Entity Tax Identification Number EBP, Plan Number EBP, Asset Held for Investment, Party-in-Interest [true false] EBP, Investment, Issuer Name [Extensible Enumeration] EBP, Investment, Current Value, Type [Extensible Enumeration] EBP, Asset Held for Investment, Investment, Excluding Plan Interest in Master Trust, Participation Status [Extensible Enumeration] EBP, Asset Held for Investment, Plan Interest in Master Trust, Current Value EBP, Asset Held for Investment, Participant Loan, Interest Rate EBP, Asset Held for Investment Common Stock [Member] Investment, Issuer Name [Axis] Investment, Issuer Name [Domain] EBP, Participant-Directed and Nonparticipant-Directed Status [Axis] EBP, Participant-Directed and Nonparticipant-Directed Status [Domain] Investment, Identifier [Axis] Allspring SpecialMidCapValue R6 [Member] Baird Core Plus Institutional Fund [Member] Baron Growth R6 [Member] Fidelity 500 Index Fund [Member] Fidelity Extended Market Index Fund [Member] Fidelity Government Money Market [Member] Fidelity Growth Co K6 [Member] Fidelity InflationProtected Bond Index Fund [Member] Fidelity U.S. Bond Index Fund [Member] Jpmorgan Equity Income Fund ClassR6 [Member] Mellon Stable Value M [Member] Mfs International Diversification Fund R4 [Member] South Bow Corporation [Member] South Bow Stock Fund [Member] Tc Energy Corporation [Member] Tc Energy Stock Fund [Member] Vanguard Federal Money Market Fund [Member] Vanguard Target Retirement 2025 [Member] Vanguard Target Retirement 2030 [Member] Vanguard Target Retirement 2035 [Member] Vanguard Target Retirement 2040 [Member] Vanguard Target Retirement 2045 [Member] Vanguard Target Retirement 2050 [Member] Vanguard Target Retirement 2055 [Member] Vanguard Target Retirement 2060 [Member] Vanguard Target Retirement 2065 [Member] Vanguard Target Retirement 2070 [Member] Vanguard Target Retirement Income Fund [Member] Vanguard Total International Stock Fund Ad [Member] Stock Purchase Account [Member] EBP, Participant-Directed [Member]