CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Current assets
Cash and cash equivalents	$ 1,129	$ 1,079
Accounts receivable, net	59,175	56,378
Accrued unbilled revenues	40,372	47,698
Inventories	14,842	21,559
Regulatory assets	13,824	16,146
Prepaid taxes	19,786	25,976
Deferred income taxes	8,900	3,138
Prepayments and other	2,226	2,387
Total current assets	160,254	174,361
Property, plant and equipment, net	1,845,767	1,828,079
Other assets
Regulatory assets	291,774	289,196
Other investments	3,751	4,042
Other	384	67
Total other assets	295,909	293,305
Total assets	2,301,930	2,295,745
Current liabilities
Current portion of long-term debt	1,168	1,131
Short-term debt	5,000	10,000
Notes payable to affiliates	500	500
Accounts payable	25,218	34,317
Accounts payable to affiliates	27,275	24,538
Dividends payable to parent	12,529	15,322
Regulatory liabilities	15,634	11,781
Environmental liabilities	17,453	17,155
Accrued interest	9,549	7,945
Other	16,379	15,778
Total current liabilities	130,705	138,467
Deferred credits and other liabilities
Deferred Tax Liabilities, Net, Noncurrent	406,150	393,569
Deferred investment tax credits	8,428	8,560
Regulatory liabilities	144,832	141,289
Environmental liabilities	77,026	77,441
Customer advances	19,162	18,480
Pension and employee benefit obligations	42,453	49,889
Other	16,220	16,347
Total deferred credits and other liabilities	$ 714,271	$ 705,575
Commitments and contingencies
Capitalization
Long-term debt	$ 661,448	$ 661,318
Common stock — 1,000,000 shares authorized of $100 par value; 933,000 shares outstanding at March 31, 2016 and Dec. 31, 2015, respectively	93,300	93,300
Additional paid in capital	394,553	394,553
Retained earnings	307,843	302,741
Accumulated other comprehensive loss	(190)	(209)
Total common stockholder’s equity	795,506	790,385
Total liabilities and equity	$ 2,301,930	$ 2,295,745