CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Net income (loss)	$ 38.9	$ (110.5)
Commodity hedging contracts:
Other comprehensive income (loss), pre-tax	91.3	72.3
Other comprehensive income (loss), related income tax	(21.8)	(27.5)
Other comprehensive income (loss), after tax	69.5	44.8
Comprehensive income (loss)	108.4	(65.7)
Less: Comprehensive income (loss) attributable to noncontrolling interests	16.0	8.8
Comprehensive income (loss) attributable to Targa Resources Corp.	92.4	(74.5)
Commodity Contracts [Member]
Commodity hedging contracts:
Change in fair value, pre-tax	64.6	66.2
Change in fair value, related income tax	(15.4)	(25.2)
Change in fair value, after tax	49.2	41.0
Settlements reclassified to revenues, pre-tax	26.7	6.1
Settlements reclassified to revenues, related income tax	(6.4)	(2.3)
Settlements reclassified to revenues, after tax	$ 20.3	$ 3.8

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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