CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 1,144	$ 1,546
Accounts receivable, net	54,340	54,031
Accrued unbilled revenues	42,792	53,638
Inventories	15,640	18,309
Regulatory assets	18,161	18,162
Prepaid taxes	26,244	25,915
Prepayments and other	3,434	3,785
Total current assets	161,755	175,386
Property, plant and equipment, net	2,000,347	1,947,637
Other assets
Regulatory assets	274,107	286,188
Other investments	2,876	2,844
Other	1,143	785
Total other assets	278,126	289,817
Total assets	2,440,228	2,412,840
Current liabilities
Current portion of long-term debt	1,096	1,123
Short-term debt	46,000	60,000
Notes payable to affiliates	500	500
Accounts payable	48,670	41,068
Accounts payable to affiliates	53,294	29,037
Dividends payable to parent	13,840	10,729
Regulatory liabilities	24,140	17,428
Environmental liabilities	29,752	41,438
Accrued interest	8,083	8,012
Other	16,651	26,484
Total current liabilities	242,026	235,819
Deferred credits and other liabilities
Deferred income taxes	454,839	430,593
Deferred investment tax credits	7,775	8,037
Regulatory liabilities	152,588	148,189
Environmental liabilities	17,146	23,003
Customer advances	16,759	19,425
Pension and employee benefit obligations	46,281	55,164
Other	18,857	18,814
Total deferred credits and other liabilities	714,245	703,225
Commitments and contingencies
Capitalization
Long-term debt	662,306	661,946
Common stock — 1,000,000 shares authorized of $100 par value; 933,000 shares outstanding at June 30, 2017 and Dec. 31, 2016, respectively	93,300	93,300
Additional paid in capital	410,329	395,315
Retained earnings	318,117	323,368
Accumulated other comprehensive loss	(95)	(133)
Total common stockholder’s equity	821,651	811,850
Total liabilities and equity	$ 2,440,228	$ 2,412,840