Debt Obligations - Summary Of Debt Obligations (Details) - USD ($) $ in Millions		Sep. 30, 2022	Dec. 31, 2021
Current:
Partnership accounts receivable securitization facility, due September 2023	[1]	$ 750.0	$ 150.0
Finance lease liabilities		16.5	12.8
Current debt obligations		766.5	162.8
Long-term [Abstract]
Long-term debt including Unamortized premium(discount) and Debt issuance costs		10,457.9	6,465.7
Debt issuance costs, net of amortization		(66.5)	(45.0)
Finance lease liabilities		39.9	13.7
Long-term debt		10,431.3	6,434.4
Total debt obligations		11,197.8	6,597.2
Letters of credit outstanding		47.2	71.3
Senior Unsecured Notes [Member]
Long-term [Abstract]
Unamortized discount		(8.5)	0.0
Senior Unsecured Notes [Member] | Senior Unsecured 5.200% fixed rate, due July 2027 [Member]
Long-term [Abstract]
Long-term debt		750.0	0.0
Senior Unsecured Notes [Member] | Senior Unsecured 5.200% fixed rate, due July 2027 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2]	705.2	705.2
Senior Unsecured Notes [Member] | Senior Unsecured 4.200% Notes due February 2033 [Member]
Long-term [Abstract]
Long-term debt		750.0	0.0
Senior Unsecured Notes [Member] | Senior Unsecured 4.950% Notes due April 2052 [Member]
Long-term [Abstract]
Long-term debt		750.0	0.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.250% fixed rate, due July 2052 [Member]
Long-term [Abstract]
Long-term debt		500.0	0.0
Senior Unsecured Notes [Member] | Senior Unsecured 5.875% Notes due April 2026 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2],[3]	0.0	963.2
Senior Unsecured Notes [Member] | Senior Unsecured 5.375% Notes due February 2027 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2],[4]	0.0	468.1
Senior Unsecured Notes [Member] | Senior Unsecured 5.000% Notes due January 2028 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2]	700.3	700.3
Senior Unsecured Notes [Member] | Senior Unsecured 6.875% Senior Notes due January 2029 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2]	679.3	679.3
Senior Unsecured Notes [Member] | Senior Unsecured 5.500% Notes due March 2030 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2]	949.6	949.6
Senior Unsecured Notes [Member] | Senior Unsecured of 4.875% Senior Notes due February 2031 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2]	1,000.0	1,000.0
Senior Unsecured Notes [Member] | Senior Unsecured of 4.000% Senior Notes due January 2032 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[2]	1,000.0	1,000.0
Term Loan Facility, Variable Rate, due July 2025
Long-term [Abstract]
Long-term debt		1,500.0	0.0
Revolving Credit Facility [Member] | TRGP Senior Revolving Credit Facility due February 2027 [Member]
Long-term [Abstract]
Long-term debt	[5]	1,182.0	0.0
Revolving Credit Facility [Member] | TRGP Senior Revolving Credit Facility due February 2027 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Letters of credit outstanding	[5]	47.2	0.0
Revolving Credit Facility [Member] | TRP Senior Revolving Credit Facility due June 2023 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Letters of credit outstanding	[5]	$ 0.0	$ 71.3

[1] In September 2022, the Partnership amended the Securitization Facility to, among other things, increase the facility size from $400.0 million to $800.0 million and extend the facility termination date to September 1, 2023. As of September 30, 2022, the Partnership had $750.0 million of qualifying receivables under its $800.0 million accounts receivable securitization facility (the “Securitization Facility”), resulting in $50.0 million of availability.

[2] As of February 2022, we guarantee all of the Partnership’s outstanding senior unsecured notes.

[3] In April 2022, the Partnership redeemed all of the outstanding 5.875% Senior Notes due 2026 (the “5.875% Notes”).

[4] In March 2022, the Partnership redeemed all of the outstanding 5.375% Senior Notes due 2027 (the “5.375% Notes”) with the available liquidity under the TRGP Revolver.

[5] In February 2022, we entered into the TRGP Revolver which matures in February 2027, and terminated our previous TRGP senior secured revolving credit facility (the “Previous TRGP Revolver”) and the Partnership’s senior secured revolving credit facility (the “Partnership Revolver”). In July 2022, we established an unsecured commercial paper note program (the “Commercial Paper Program”), the borrowings of which are supported through maintaining a minimum available borrowing capacity under our TRGP Revolver equal to the aggregate amount outstanding under the Commercial Paper Program. As of September 30, 2022, the TRGP Revolver had $550.0 million borrowings outstanding and the Commercial Paper Program had $632.0 million borrowings outstanding, resulting in approximately $1.5 billion of available liquidity, after accounting for outstanding letters of credit. As of December 31, 2021, we had no balance outstanding under the Previous TRGP Revolver or the Partnership Revolver.