Debt Obligations - Schedule of Contractual Maturities of Debt Obligations (Details) $ in Millions	Dec. 31, 2021 USD ($)
Contractual Obligation [Line Items]
Total	$ 6,615.7
2022	150.0
2023	0.0
2024	0.0
2025	0.0
2026	963.2
Thereafter	5,502.5
Securitization Facility \| Targa Resources Partners LP [Member]
Contractual Obligation [Line Items]
Total	150.0
2022	150.0
2023	0.0
2024	0.0
2025	0.0
2026	0.0
Thereafter	0.0
Senior Unsecured Notes [Member] \| Targa Resources Partners LP [Member]
Contractual Obligation [Line Items]
Total	6,465.7
2022	0.0
2023	0.0
2024	0.0
2025	0.0
2026	963.2
Thereafter	5,502.5
Existing TRC Revolver [Member]
Contractual Obligation [Line Items]
Total	0.0
2022	0.0
2023	0.0
2024	0.0
2025	0.0
2026	0.0
Thereafter	0.0
Existing TRP Revolver [Member]
Contractual Obligation [Line Items]
Total	0.0
2022	0.0
2023	0.0
2024	0.0
2025	0.0
2026	0.0
Thereafter	$ 0.0

Contractual obligation.

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Total amount, before unamortized (discount) premium and debt issuance costs, of long-term debt.

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