STATEMENTS OF INCOME (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
OPERATING REVENUES	$ 2,262.2	$ 2,141.2	$ 2,211.5
COST OF SALES	965.9	879.1	1,013.5
OPERATING EXPENSES
Other operation and maintenance	438.8	446.3	436.0
Depreciation and amortization	248.4	248.7	216.1
Taxes other than income	83.8	77.7	73.6
Total operating expenses	771.0	772.7	725.7
OPERATING INCOME	525.3	489.4	472.3
OTHER INCOME (EXPENSE)
Allowance for borrowed funds used during construction	6.6	6.2	20.4
Other income	8.1	8.2	8.5
Other expense	(4.6)	(4.3)	(8.4)
Net other income (expense)	10.1	10.1	20.5
INTEREST EXPENSE
Interest on long-term debt	130.6	124.2	118.7
Allowance for borrowed funds used during construction	(3.4)	(3.5)	(10.4)
Interest on short-term debt and other interest charges	2.1	3.9	3.3
Interest expense	129.3	124.6	111.6
INCOME BEFORE TAXES	406.1	374.9	381.2
INCOME TAX EXPENSE	113.5	94.6	117.9
NET INCOME	$ 292.6	$ 280.3	$ 263.3