Statements of Consolidated Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 19.2	$ 20.7	$ 47.2	$ 46.4
Other comprehensive (loss) income, net of tax:
Defined benefit pension plan and Salaried VEBA	1.1	1.2	2.2	2.4
Available for sale securities	(0.1)	(0.1)	(0.3)	(0.3)
Cash flow hedges	(4.2)	5.3	4.6	(4.0)
Other comprehensive (loss) income, net of tax	(3.2)	6.4	6.5	(1.9)
Comprehensive income	$ 16.0	$ 27.1	$ 53.7	$ 44.5

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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