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No definition available.

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No definition available.

Name:	trgp_DerivativeAssetBeforeEffectsOfMasterNettingArrangementsNoncurrent
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Data Type:	xbrli:monetaryItemType
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Fair value, before the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

No definition available.

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Data Type:	xbrli:monetaryItemType
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No definition available.

Name:	trgp_DerivativeLiabilityBeforeEffectsOfMasterNettingArrangementsCurrent
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Data Type:	xbrli:monetaryItemType
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No definition available.

Name:	trgp_DerivativeLiabilityBeforeEffectsOfMasterNettingArrangementsNoncurrent
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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.

Name:	us-gaap_DerivativesFairValueLineItems
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Name:	us-gaap_BalanceSheetLocationAxis=us-gaap_OtherCurrentAssetsMember
Namespace Prefix:
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