Consolidated Condensed Income Statements (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Operating Revenues	$ 991.2	$ 1,043.7	$ 2,379.1	$ 2,738.7
Operating Expenses
Fuel and purchased power	273.7	292.5	571.4	611.1
Cost of gas sold	79.3	125.9	395.5	717.4
Other operation and maintenance	337.0	256.0	617.7	531.4
Depreciation and amortization	105.7	101.4	210.8	202.0
Property and revenue taxes	31.9	30.3	63.8	60.9
Total Operating Expenses	827.6	806.1	1,859.2	2,122.8
Treasury Grant	2.2	3.1	4.7	6.6
Operating Income	165.8	240.7	524.6	622.5
Equity in Earnings of Unconsolidated Affiliates	14.2	17.5	30.3	34.8
Other Income, net	26.1	8.1	29.1	9.2
Interest Expense, net	62.1	59.0	121.8	121.3
Income from Continuing Operations Before Income Taxes	144.1	207.3	462.3	545.2
Income Tax Expense	63.2	74.3	185.6	204.6
Net Income	$ 80.9	$ 133.0	$ 276.7	$ 340.6
Earnings Per Share (Basic)
Continuing operations	$ 0.36	$ 0.59	$ 1.22	$ 1.51
Earnings Per Share (Diluted)
Continuing operations	$ 0.35	$ 0.58	$ 1.21	$ 1.50
Weighted Average Common Shares Outstanding (Millions)
Basic	227.5	225.5	226.5	225.6
Diluted	229.1	227.6	228.2	227.7
Dividends Per Share of Common Stock	$ 0.8629
Transmission Affiliate [Member]
Operating Expenses
Equity in Earnings of Unconsolidated Affiliates	$ 14.3	$ 17.5	$ 30.4	$ 34.8