Derivative Instruments and Hedging Activities - Notional Volumes Of The Partnership's Commodity Derivative Contracts (Details) - Targa Resources Partners LP [Member]	9 Months Ended
Sep. 30, 2026 MMBTU bbl
Swaps [Member] \| Year 2026 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	79,505
Swaps [Member] \| Year 2026 [Member] \| NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	42,864
Swaps [Member] \| Year 2026 [Member] \| Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	8,263
Swaps [Member] \| Year 2027 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	77,778
Swaps [Member] \| Year 2027 [Member] \| NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	28,962
Swaps [Member] \| Year 2027 [Member] \| Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	7,034
Swaps [Member] \| Year 2028 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	77,230
Swaps [Member] \| Year 2028 [Member] \| NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	22,864
Swaps [Member] \| Year 2028 [Member] \| Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	11,487
Swaps [Member] \| Year 2029 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	30,647
Swaps [Member] \| Year 2029 [Member] \| NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	11,328
Swaps [Member] \| Year 2029 [Member] \| Condensate [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	5,861
Basis Swaps [Member] \| Year 2026 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	537,717
Basis Swaps [Member] \| Year 2027 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	547,116
Basis Swaps [Member] \| Year 2028 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	394,053
Basis Swaps [Member] \| Year 2029 [Member] \| Natural Gas [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in MMBtu per day) \| MMBTU	44,959
Future [Member] \| Year 2026 [Member] \| NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	62,457
Future [Member] \| Year 2027 [Member] \| NGL [Member]
Derivative [Line Items]
Notional volumes of commodity hedges (in Bbl per day)	3,474

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.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-18

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-5

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Nominal volume used to calculate payments on a derivative instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

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