Debt Obligations - Summary Of Debt Obligations (Details) - USD ($) $ in Millions		Mar. 31, 2025	Feb. 28, 2025	Dec. 31, 2024
Current:
Partnership accounts receivable securitization facility, due August 2025	[1]	$ 600.0		$ 330.0
Finance lease liabilities		60.4		57.7
Current debt obligations		660.4		387.7
Long-term [Abstract]
Long-term debt including Unamortized premium(discount) and Debt issuance costs		15,419.2		13,635.5
Debt issuance costs, net of amortization		(106.7)		(89.0)
Finance lease liabilities		235.8		240.4
Long-term debt		15,548.3		13,786.9
Total debt obligations		16,208.7		14,174.6
Senior Unsecured Notes [Member]
Long-term [Abstract]
Unamortized discount		(35.2)	$ (6.1)	(29.4)
Senior Unsecured Notes [Member] | Senior Unsecured 5.200% Fixed Rate, due July 2027 [Member]
Long-term [Abstract]
Long-term debt		750.0		750.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.150% Fixed Rate, due March 2029 [Member]
Long-term [Abstract]
Long-term debt		1,000.0		1,000.0
Senior Unsecured Notes [Member] | Senior Unsecured 4.200% Notes due February 2033 [Member]
Long-term [Abstract]
Long-term debt		750.0		750.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.125% Fixed Rate, due March 2033 [Member]
Long-term [Abstract]
Long-term debt		900.0		900.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.500% Fixed Rate, due March 2034 [Member]
Long-term [Abstract]
Long-term debt		1,000.0		1,000.0
Senior Unsecured Notes [Member] | Senior Unsecured 5.500% Fixed Rate, due February 2035 [Member]
Long-term [Abstract]
Long-term debt		1,000.0		1,000.0
Senior Unsecured Notes [Member] | Senior Unsecured 5.500% Fixed Rate, due August 2035 [Member]
Long-term [Abstract]
Long-term debt	[2]	1,000.0
Senior Unsecured Notes [Member] | Senior Unsecured 4.950% Notes due April 2052 [Member]
Long-term [Abstract]
Long-term debt		750.0		750.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.250% fixed rate, due July 2052 [Member]
Long-term [Abstract]
Long-term debt		500.0		500.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.500% Fixed Rate, due February 2053 [Member]
Long-term [Abstract]
Long-term debt		850.0		850.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.125% Fixed Rate, due May 2055 [Member]
Long-term [Abstract]
Long-term debt	[2]	1,000.0
Senior Unsecured Notes [Member] | Senior Unsecured 6.500% Fixed Rate, due July 2027 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[3]	705.2		705.2
Senior Unsecured Notes [Member] | Senior Unsecured 5.000% Notes due January 2028 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[3]	700.3		700.3
Senior Unsecured Notes [Member] | Senior Unsecured of 6.875% Senior Notes due January 2029 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[3]	679.3		679.3
Senior Unsecured Notes [Member] | Senior Unsecured of 5.500% Senior Notes due March 2030 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Long-term debt	[3]	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	[3]	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	[3]	1,000.0		1,000.0
Revolving Credit Facility [Member] | TRGP Senior Revolving Credit Facility due February 2030 [Member]
Long-term [Abstract]
Long-term debt	[4]	920.0		1,130.5
Revolving Credit Facility [Member] | TRGP Senior Revolving Credit Facility due February 2030 [Member] | Targa Resources Partners LP [Member]
Long-term [Abstract]
Letters of credit outstanding	[4]	$ 9.4		$ 17.6

[1] As of March 31, 2025, the Partnership had $600.0 million of qualifying receivables under its $600.0 million accounts receivable securitization facility (the “Securitization Facility”), resulting in no remaining availability.

[2] In February 2025, we completed an underwritten public offering of (i) $1.0 billion aggregate principal amount of our 5.550% Senior Unsecured Notes due 2035 (the “5.550% Notes due 2035”) and (ii) $1.0 billion aggregate principal amount of our 6.125% Senior Unsecured Notes due 2055 (the “6.125% Notes due 2055”), resulting in net proceeds of approximately $2.0 billion.

[3] We guarantee all of the Partnership’s outstanding senior unsecured notes.

[4] In February 2025, we entered into a new $3.5 billion TRGP senior revolving credit facility (the “TRGP Revolver”), which matures in February 2030. In connection with our entry into the TRGP Revolver, we terminated our previous TRGP senior revolving credit facility (the “Previous TRGP Revolver”). We maintain 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 at any one time not to exceed $3.5 billion, subject to final documentation requirements completed in April 2025. The TRGP Revolver had no borrowings outstanding and the Commercial Paper Program had $920.0 million borrowings outstanding, resulting in approximately $2.6 billion of available liquidity as of March 31, 2025, after accounting for outstanding letters of credit.