CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 96.7	$ 130.7
Adjustments to reconcile net income to net cash provided from operating activities
Depreciation and amortization	158.6	152.1
Deferred income taxes and investment tax credits	52.2	48.1
Equity in earnings of unconsolidated affiliates	(45.0)	(59.9)
Distributions from unconsolidated affiliates	45.4	68.9
Allowance for equity funds used during construction	(5.3)	(3.2)
Stock-based compensation	3.2	2.4
Regulatory assets	(4.0)	2.5
Regulatory liabilities	(8.4)	(2.0)
Other assets	6.8	4.5
Other liabilities	5.7	(2.4)
Change in certain current assets and liabilities
Accounts receivable, net	10.0	2.9
Accounts receivable - unconsolidated affiliates	3.1	3.2
Accrued unbilled revenues	(37.4)	(30.8)
Fuel, materials and supplies inventories	11.2	(29.7)
Fuel clause under recoveries	0.0	64.6
Other current assets	(17.7)	(10.2)
Accounts payable	(56.8)	(40.7)
Fuel clause over recoveries	(20.0)	1.6
Other current liabilities	(32.3)	3.2
Net Cash Provided from Operating Activities	166.0	305.8
CASH FLOWS FROM INVESTING ACTIVITIES
Capital expenditures (less allowance for equity funds used during construction)	(331.1)	(227.7)
Return of capital - equity method investments	25.2	0.0
Proceeds from sale of assets	0.2	2.0
Net Cash Used in Investing Activities	(305.7)	(225.7)
CASH FLOWS FROM FINANCING ACTIVITIES
Dividends paid on common stock	(109.8)	(99.8)
Issuance of common stock	0.0	6.8
Payment of long-term debt	(110.1)	(0.1)
Increase in short-term debt	284.4	7.5
Net Cash Provided from (Used in) Financing Activities	64.5	(85.6)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(75.2)	(5.5)
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	75.2	5.5
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 0.0	$ 0.0