CONDENSED CONSOLIDATED BALANCE SHEETS (USD $) In Millions, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Assets
Cash and cash equivalents	$ 20.2	$ 27.4
Collateral on deposit	60.3	41.0
Accounts receivable and accrued unbilled revenues, net of reserves of $48.7 and $43.5, respectively	688.2	796.8
Inventories	206.3	271.9
Current assets from risk management activities	181.8	145.4
Regulatory assets	102.3	110.8
Assets held for sale	1.5	10.1
Deferred income taxes	2.2	64.3
Prepaid taxes	191.0	152.8
Other current assets	34.9	38.6
Current assets	1,488.7	1,659.1
Property, plant, and equipment, net of accumulated depreciation of $3,269.1 and $3,114.7, respectively	6,062.6	5,501.9
Regulatory assets	1,824.5	1,813.8
Long-term Assets from Risk Management Activities	62.1	45.3
Equity method investments	527.5	512.2
Goodwill	662.1	658.3
Other long-term assets	149.5	136.8
Total assets	10,777.0	10,327.4
Liabilities and Equity
Short-term debt	833.2	482.4
Current portion of long-term debt	276.5	313.5
Accounts payable	484.7	457.7
Current Liabilities from Risk Management Activities	198.1	181.9
Accrued taxes	50.5	83.0
Regulatory liabilities	73.8	65.6
Liabilities held for sale	0	0.2
Other current liabilities	211.3	229.0
Current liabilities	2,128.1	1,813.3
Long-term debt	1,886.2	1,931.7
Deferred income taxes	1,298.4	1,203.8
Deferred investment tax credits	48.5	49.3
Regulatory liabilities	377.9	370.5
Environmental remediation liabilities	629.6	651.5
Pension and other postretirement benefit obligations	569.6	625.2
Long-term Liabilities from Risk Management Activities	64.3	58.4
Asset retirement obligations	421.5	411.2
Other long-term liabilities	147.1	135.7
Long-term liabilities	5,443.1	5,437.3
Commitments and Contingencies
Common stock – $1 par value; 200,000,000 shares authorized; 79,456,539 shares issued; 78,994,158 shares outstanding	79.5	78.3
Additional paid-in capital	2,627.0	2,574.6
Retained earnings	506.0	431.5
Accumulated other comprehensive loss	(36.6)	(40.9)
Shares in deferred compensation trust	(22.3)	(17.7)
Total common shareholders' equity	3,153.6	3,025.8
Preferred stock of subsidiary – $100 par value; 1,000,000 shares authorized; 511,882 shares issued; 510,495 shares outstanding	51.1	51.1
Noncontrolling interest in subsidiaries	1.1	(0.1)
Total liabilities and equity	$ 10,777.0	$ 10,327.4