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The cash payment paid for each unit holder of the acquiree.

No definition available.

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Refers to the cash payment related to one-time cash payments and cash settlements of equity awards in association with the business acquisition.

No definition available.

Name:	trgp_BusinessAcquisitionCashPaymentRelatedToOneTimeCashPaymentsAndCashSettlementsOfEquityAwards
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Refers to the increase (decrease) in amount of consideration transferred in a business acquisition.

No definition available.

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Number of shares of equity interests issued or issuable for each common unit to acquire entity.

No definition available.

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Period Type:	duration

Refers to common units owned by parent immediately prior to closing.

No definition available.

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The amount of capital contributed by the general partner during the period to maintain general partner ownership.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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The increase (decrease) on quarterly basis in incentive distribution.

No definition available.

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Balance Type:	debit
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Refers to the length of pipelines.

No definition available.

Name:	trgp_LengthOfPipelines
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The percentage of ownership interest in common stock of spin-off entity.

No definition available.

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Refers to the processing capacity of gas plants.

No definition available.

Name:	trgp_ProcessingCapacityOfGasPlants
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Value of equity interests (such as common shares, preferred shares, or partnership interest) issued or issuable to acquire the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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Number of shares of equity interests issued or issuable to acquire entity.

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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.

No definition available.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

No definition available.

Name:	us-gaap_BusinessAcquisitionSharePrice
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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 23
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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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-Publisher FASB
-Name Accounting Standards Codification
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This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Face amount or stated value per share of common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

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-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_LimitedLiabilityCompanyLLCOrLimitedPartnershipLPManagingMemberOrGeneralPartnerOwnershipInterest
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

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Data Type:	xbrli:monetaryItemType
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The percentage rate used to calculate dividend payments on preferred stock.

No definition available.

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Data Type:	num:percentItemType
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Additional share-based compensation cost recognized as a result of an occurrence of an event that accelerates its recognition.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=trgp_TargaPipelinePartnersLPMember
Namespace Prefix:
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Name:	dei_LegalEntityAxis=trgp_TargaResourcesPartnersLpMember
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Name:	us-gaap_BusinessAcquisitionAxis=trgp_AtlasEnergyLPAcquisitionMember
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Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CapitalUnitsMember
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Name:	us-gaap_AwardTypeAxis=trgp_PhantomUnitAwardsMember
Namespace Prefix:
Data Type:	na
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Namespace Prefix:
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Name:	us-gaap_AwardTypeAxis=trgp_EquityAwardSettlementsMember
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Name:	us-gaap_BusinessAcquisitionAxis=trgp_AtlasPipelinePartnersLPAcquisitionMember
Namespace Prefix:
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Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_StatementClassOfStockAxis=us-gaap_SeriesEPreferredStockMember
Namespace Prefix:
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Name:	us-gaap_CreditFacilityAxis=trgp_ChangeOfControlPaymentsMember
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Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=us-gaap_InvestorMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_IncentiveDistributionMadeToManagingMemberOrGeneralPartnerAxis=trgp_IncentiveDistributionRightsYearOneMember
Namespace Prefix:
Data Type:	na
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Name:	us-gaap_IncentiveDistributionMadeToManagingMemberOrGeneralPartnerAxis=trgp_IncentiveDistributionRightsYearTwoMember
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