CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
CURRENT ASSETS
Cash and cash equivalents	$ 2.3	$ 14.4
Accounts receivable, less reserve of $1.0 and $1.5, respectively	177.6	188.7
Accounts receivable - affiliates	6.9	1.9
Accrued unbilled revenues	57.8	66.5
Income taxes receivable	6.3	5.8
Fuel inventories	95.4	84.3
Materials and supplies, at average cost	101.4	80.8
Other	45.8	54.6
Total current assets	493.5	497.0
OTHER PROPERTY AND INVESTMENTS
Investment in unconsolidated affiliates	1,160.6	1,160.4
Other	76.2	76.7
Total other property and investments	1,236.8	1,237.1
PROPERTY, PLANT AND EQUIPMENT
In service	11,474.4	11,041.2
Construction work in progress	525.7	867.5
Total property, plant and equipment	12,000.1	11,908.7
Less accumulated depreciation	3,607.0	3,568.8
Net property, plant and equipment	8,393.1	8,339.9
DEFERRED CHARGES AND OTHER ASSETS
Regulatory assets	275.6	283.0
Other	37.4	55.7
Total deferred charges and other assets	313.0	338.7
TOTAL ASSETS	10,436.4	10,412.7
CURRENT LIABILITIES
Short-term debt	193.9	168.4
Accounts payable	181.0	230.4
Dividends payable	66.4	66.4
Customer deposits	81.4	80.7
Accrued taxes	31.4	44.5
Accrued interest	38.9	44.0
Accrued compensation	25.7	35.9
Long-term debt due within one year	499.7	249.8
Fuel clause over recoveries	49.9	1.7
Other	46.9	28.7
Total current liabilities	1,215.2	950.5
LONG-TERM DEBT	2,500.1	2,749.6
DEFERRED CREDITS AND OTHER LIABILITIES
Accrued benefit obligations	190.4	192.7
Deferred income taxes	1,232.3	1,227.8
Regulatory liabilities	1,292.7	1,283.4
Other	163.6	157.6
Total deferred credits and other liabilities	2,879.0	2,861.5
Total liabilities	6,594.3	6,561.6
COMMITMENTS AND CONTINGENCIES (NOTE 13)
STOCKHOLDERS' EQUITY
Common stockholders' equity	1,117.1	1,114.8
Retained earnings	2,748.0	2,759.5
Accumulated other comprehensive loss, net of tax	(23.0)	(23.2)
Total stockholders' equity	3,842.1	3,851.1
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 10,436.4	$ 10,412.7

Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Balance Type:	credit
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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.