Consolidated Condensed Statements of Cash Flows (Unaudited) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating Activities
Net Income	$ 176.6	$ 172.1
Reconciliation to cash
Depreciation and amortization	98.2	90.6
Deferred income taxes and investment tax credits, net	42.8	67.9
Contributions to qualified benefit plans	0	0
Change in -
Accounts receivable and accrued revenues	(84.3)	11.5
Inventories	93.9	70.4
Other current assets	28.2	29.8
Accounts payable	(104.5)	(82.3)
Accrued income taxes, net	46.2	15.5
Other current liabilities	35.6	15.2
Other, net	(2.4)	(50.2)
Cash Provided by Operating Activities	330.3	340.5
Investing Activities
Capital expenditures	(133.6)	(142.3)
Investment in transmission affiliate	(1.3)	(2.6)
Change in restricted cash	2.7	20.8
Other, net	(13.1)	(6.3)
Cash Used in Investing Activities	(145.3)	(130.4)
Financing Activities
Exercise of stock options	27.3	12.9
Purchase of common stock	(66.5)	(29.2)
Dividends paid on common stock	(77.8)	(69.1)
Retirement and repurchase of long-term debt	(8.5)	(8.0)
Change in short-term debt	(77.9)	(112.6)
Other, net	7.5	(0.1)
Cash Used in Financing Activities	(195.9)	(206.1)
Change in Cash and Cash Equivalents	(10.9)	4.0
Cash and Cash Equivalents at Beginning of Period	35.6	14.1
Cash and Cash Equivalents at End of Period	$ 24.7	$ 18.1