CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 1,592	$ 1,079
Accounts receivable, net	51,779	56,378
Accrued unbilled revenues	41,626	47,698
Inventories	16,130	21,559
Regulatory assets	13,891	16,146
Prepaid taxes	25,827	25,976
Deferred income taxes	7,770	3,138
Prepayments and other	2,354	2,387
Total current assets	160,969	174,361
Property, plant and equipment, net	1,869,115	1,828,079
Other assets
Regulatory assets	294,634	289,196
Other investments	3,354	4,042
Other	459	67
Total other assets	298,447	293,305
Total assets	2,328,531	2,295,745
Current liabilities
Current portion of long-term debt	1,153	1,131
Short-term debt	8,000	10,000
Notes payable to affiliates	500	500
Accounts payable	31,801	34,317
Accounts payable to affiliates	29,255	24,538
Dividends payable to parent	10,563	15,322
Regulatory liabilities	19,571	11,781
Environmental liabilities	18,956	17,155
Accrued interest	7,914	7,945
Other	14,505	15,778
Total current liabilities	142,218	138,467
Deferred credits and other liabilities
Deferred Tax Liabilities, Net, Noncurrent	414,948	393,569
Deferred investment tax credits	8,296	8,560
Regulatory liabilities	146,849	141,289
Environmental liabilities	76,330	77,441
Customer advances	18,738	18,480
Pension and employee benefit obligations	42,869	49,889
Other	16,414	16,347
Total deferred credits and other liabilities	724,444	705,575
Commitments and contingencies
Capitalization
Long-term debt	661,629	661,318
Common stock — 1,000,000 shares authorized of $100 par value; 933,000 shares outstanding at June 30, 2016 and Dec. 31, 2015, respectively	93,300	93,300
Additional paid in capital	397,205	394,553
Retained earnings	309,906	302,741
Accumulated other comprehensive loss	(171)	(209)
Total common stockholder’s equity	800,240	790,385
Total liabilities and equity	$ 2,328,531	$ 2,295,745