CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Net income (loss)	$ (24.7)	$ 38.9
Commodity hedging contracts:
Other comprehensive income (loss), pre-tax	(60.1)	91.3
Other comprehensive income (loss), related income tax	14.7	(21.8)
Other comprehensive income (loss), after tax	(45.4)	69.5
Comprehensive income (loss)	(70.1)	108.4
Less: Comprehensive income (loss) attributable to noncontrolling interests	14.2	16.0
Comprehensive income (loss) attributable to Targa Resources Corp.	(84.3)	92.4
Commodity Contracts [Member]
Commodity hedging contracts:
Change in fair value, pre-tax	(38.8)	64.6
Change in fair value, related income tax	9.5	(15.4)
Change in fair value, after tax	(29.3)	49.2
Settlements reclassified to revenues, pre-tax	(21.3)	26.7
Settlements reclassified to revenues, related income tax	5.2	(6.4)
Settlements reclassified to revenues, after tax	$ (16.1)	$ 20.3

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