Name:	trgp_DerivativeFairValueOfAssetLiabilityNetIfCommodityPriceDecreasesBy10Percent
Namespace Prefix:	trgp_
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Period Type:	instant

Fair value as of the balance sheet date of the assets less the liabilities of a derivative or group of derivatives if the commodity price increases by 10 percent.

No definition available.

Name:	trgp_DerivativeFairValueOfAssetLiabilityNetIfCommodityPriceIncreasesBy10Percent
Namespace Prefix:	trgp_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

This line item represents the number of natural gas basis swaps categorized as Level 3 by the entity.

No definition available.

Name:	trgp_NumberOfNaturalGasBasisSwapsCategorizedAsLevel3
Namespace Prefix:	trgp_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

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Fair value of the assets less the liabilities of a derivative or group of derivatives.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

Name:	us-gaap_DerivativeFairValueOfDerivativeNet
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- References

No definition available.