Leverage ratio before collateral release date.

No definition available.

Name:	trgp_LeverageRatioBeforeCollateralReleaseDate
Namespace Prefix:	trgp_
Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentTerm
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_DebtInstrumentAxis=trgp_TermLoanFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
Namespace Prefix:
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Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=trgp_NonCreditEnhancedSeniorUnsecuredLongTermDebtRatingsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=trgp_FederalFundsRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrOvernightIndexSwapRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_BaseRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_UnsecuredDebtMember
Namespace Prefix:
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Debt Obligations - Term Loan Facility - Additional Information (Details) - Term Loan Facility [Member] - USD ($)	1 Months Ended	6 Months Ended
	Jul. 31, 2022	Jun. 30, 2022
Debt Instrument [Line Items]
Interest rate, description		The Term Loan Facility bears interest at the Company’s option at: (a) the Base Rate (as defined in the Term Loan Facility), which is the highest of the (i) federal funds rate plus 0.5%, (ii) Mizuho’s prime rate, and (iii) the Term SOFR (as defined in the Term Loan Facility) rate plus 1.0% (subject in each case to a floor of 0.0%), plus an applicable margin ranging from 0.125% to 0.75% dependent on the Company’s non-credit-enhanced senior unsecured long-term debt ratings (or, if no such debt is outstanding at such time, then the corporate, issuer or similar rating with respect to the Company that has been most recently announced) (the “Debt Rating”), or (b) Term SOFR plus 0.10% plus an applicable margin ranging from 1.125% to 1.75% dependent on the Debt Rating.
Subsequent Event [Member]
Debt Instrument [Line Items]
Term loan facility, term	3 years
Maturity date	Jul. 31, 2025
Basis spread on variable rate	0.00%
Subsequent Event [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Leverage ratio before collateral release date	1.00
Subsequent Event [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Leverage ratio before collateral release date	5.50
Subsequent Event [Member] \| Non-Credit-Enhanced Senior Unsecured Long-Term Debt Ratings [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.125%
Subsequent Event [Member] \| Non-Credit-Enhanced Senior Unsecured Long-Term Debt Ratings [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Subsequent Event [Member] \| Federal Funds Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.50%
Subsequent Event [Member] \| Term SOFR Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	1.00%
Subsequent Event [Member] \| Term SOFR Rate [Member] \| Non-Credit-Enhanced Senior Unsecured Long-Term Debt Ratings [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.10%
Subsequent Event [Member] \| Base Rate [Member] \| Non-Credit-Enhanced Senior Unsecured Long-Term Debt Ratings [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.125%
Subsequent Event [Member] \| Base Rate [Member] \| Non-Credit-Enhanced Senior Unsecured Long-Term Debt Ratings [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate	0.75%
Unsecured Debt [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Aggregate principal amount issued	$ 1,500,000,000