CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 10,802	$ 1,285
Accounts receivable, net	50,370	60,396
Accrued unbilled revenues	40,910	53,567
Inventories	21,838	24,685
Regulatory assets	14,626	20,036
Prepaid taxes	18,421	28,628
Deferred income taxes	7,724	8,201
Prepayments and other	2,872	6,918
Total current assets	167,563	203,716
Property, plant and equipment, net	1,789,334	1,674,281
Other assets
Regulatory assets	276,552	280,693
Other investments	3,908	3,818
Other	5,415	4,612
Total other assets	285,875	289,123
Total assets	2,242,772	2,167,120
Current liabilities
Current portion of long-term debt	1,196	1,235
Short-term debt	0	78,000
Notes payable to affiliates	500	500
Accounts payable	32,777	61,530
Accounts payable to affiliates	26,471	26,524
Dividends payable to parent	13,664	14,957
Regulatory liabilities	10,765	16,940
Environmental liabilities	16,689	29,116
Other	24,379	19,923
Total current liabilities	126,441	248,725
Deferred credits and other liabilities
Deferred income taxes	390,095	348,180
Deferred investment tax credits	8,692	9,089
Regulatory liabilities	141,659	132,674
Environmental liabilities	79,153	78,620
Customer advances	18,080	17,623
Pension and employee benefit obligations	47,336	51,313
Other	16,330	16,151
Total deferred credits and other liabilities	$ 701,345	$ 653,650
Commitments and contingencies
Capitalization
Long-term debt	$ 666,379	$ 567,056
Common stock — 1,000,000 shares authorized of $100 par value; 933,000 shares outstanding at Sept. 30, 2015 and Dec. 31, 2014, respectively	93,300	93,300
Additional paid in capital	351,097	322,276
Retained earnings	304,438	282,398
Accumulated other comprehensive loss	(228)	(285)
Total common stockholder’s equity	748,607	697,689
Total liabilities and equity	$ 2,242,772	$ 2,167,120