Debt Obligations - Schedule of Contractual Maturities of Debt Obligations (Details) $ in Millions	Dec. 31, 2020 USD ($)
Contractual Obligation [Line Items]
Total	$ 7,770.4
2021	356.5
2022	0.0
2023	1,467.0
2024	0.0
2025	481.0
After 2025	5,465.9
Securitization Facility \| Targa Resources Partners LP [Member]
Contractual Obligation [Line Items]
Total	350.0
2021	350.0
2022	0.0
2023	0.0
2024	0.0
2025	0.0
After 2025	0.0
Senior Unsecured Notes [Member] \| Targa Resources Partners LP [Member]
Contractual Obligation [Line Items]
Total	6,585.4
2021	6.5
2022	0.0
2023	632.0
2024	0.0
2025	481.0
After 2025	5,465.9
TRC Revolver [Member]
Contractual Obligation [Line Items]
Total	555.0
2021	0.0
2022	0.0
2023	555.0
2024	0.0
2025	0.0
After 2025	0.0
TRP Revolver [Member]
Contractual Obligation [Line Items]
Total	280.0
2021	0.0
2022	0.0
2023	280.0
2024	0.0
2025	0.0
After 2025	$ 0.0

Contractual obligation.

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+ References

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e24072-122690

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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