CONDENSED STATEMENTS OF INCOME AND COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue from Contract with Customer, Excluding Assessed Tax	$ 477.9	$ 0.0
Revenues from Alternative Revenue Programs	14.8	0.0
Operating revenues	492.7	456.0
COST OF SALES	210.5	208.7
OPERATING EXPENSES
Other operation and maintenance	119.7	124.7
Depreciation and amortization	78.8	54.7
Taxes other than income	22.7	22.3
Total operating expenses	221.2	201.7
OPERATING INCOME	61.0	45.6
OTHER INCOME (EXPENSE)
Allowance for equity funds used during construction	7.0	6.9
Pension and Other Postretirement Benefits Cost (Reversal of Cost)	1.3	(1.4)
Other income	3.1	6.4
Other expense	(0.8)	(0.4)
Net other income	10.6	11.5
INTEREST EXPENSE
Interest on long-term debt	39.6	35.5
Allowance for borrowed funds used during construction	(3.7)	(3.3)
Interest on short-term debt and other interest charges	1.4	1.4
Interest expense	37.3	33.6
INCOME BEFORE TAXES	34.3	23.5
INCOME TAX EXPENSE	3.0	7.3
NET INCOME	31.3	16.2
Other comprehensive income (loss), net of tax	0.0	0.0
COMPREHENSIVE INCOME	$ 31.3	$ 16.2