CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenues:
Total revenues	$ 3,415.9	$ 1,523.5	$ 7,048.7	$ 3,572.4
Costs and expenses:
Product purchases and fuel	2,709.0	880.1	5,545.3	2,082.2
Operating expenses	184.8	163.9	355.8	344.7
Depreciation and amortization expense	211.9	204.5	428.0	443.6
General and administrative expense	63.7	61.5	125.1	121.9
Impairment of long-lived assets				2,442.8
Other operating (income) expense	0.7	0.4	4.6	1.6
Income (loss) from operations	245.8	213.1	589.9	(1,864.4)
Other income (expense):
Interest expense, net	(94.8)	(96.7)	(193.2)	(194.7)
Equity earnings (loss)	12.8	14.9	24.6	35.5
Gain (loss) from financing activities	(1.9)	21.8	(16.6)	61.1
Other, net	0.1	0.8	0.2	0.8
Income (loss) before income taxes	162.0	153.9	404.9	(1,961.7)
Income tax (expense) benefit	(6.6)	23.2	(21.6)	318.5
Net income (loss)	155.4	177.1	383.3	(1,643.2)
Less: Net income (loss) attributable to noncontrolling interests	99.2	96.1	180.7	13.6
Net income (loss) attributable to Targa Resources Corp.	56.2	81.0	202.6	(1,656.8)
Dividends on Series A Preferred Stock	21.8	22.9	43.7	45.8
Deemed dividends on Series A Preferred Stock		9.2		18.2
Net income (loss) attributable to common shareholders	$ 34.4	$ 48.9	$ 158.9	$ (1,720.8)
Net income (loss) per common share - basic	$ 0.15	$ 0.21	$ 0.70	$ (7.38)
Net income (loss) per common share - diluted	$ 0.15	$ 0.21	$ 0.69	$ (7.38)
Weighted average shares outstanding - basic	228.6	233.1	228.5	233.1
Weighted average shares outstanding - diluted	231.3	233.8	230.9	233.1
Sales of Commodities [Member]
Revenues:
Total revenues	$ 3,091.6	$ 1,280.6	$ 6,459.3	$ 3,060.2
Fees from Midstream Services [Member]
Revenues:
Total revenues	$ 324.3	$ 242.9	$ 589.4	$ 512.2