CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 1,700	$ 2,200
Accounts receivable, net	72,900	75,100
Accrued unbilled revenues	45,600	56,200
Other Receivables	6,700	6,800
Inventories	11,700	17,100
Regulatory assets	21,500	22,600
Prepaid taxes	18,300	30,200
Prepayments and other	4,100	3,300
Total current assets	182,500	213,500
Property, Plant and Equipment, Net [Abstract]
Property, plant and equipment	2,249,400	2,241,600
Other assets
Regulatory assets	282,000	285,500
Other investments	2,800	2,700
Other	200	200
Total other assets	285,000	288,400
Total assets	2,716,900	2,743,500
Current liabilities
Short-term debt	49,000	51,000
Notes payable to affiliates	0	600
Accounts payable	29,000	56,800
Accounts payable to affiliates	21,800	20,000
Dividends payable to parent	14,400	17,400
Regulatory liabilities	23,900	20,900
Taxes Payable, Current	12,000	3,000
Environmental liabilities	11,500	10,900
Accrued interest	7,700	8,800
Other	12,600	14,800
Total current liabilities	181,900	204,200
Deferred credits and other liabilities
Deferred income taxes	280,300	280,700
Deferred investment tax credits	6,900	7,000
Regulatory liabilities	404,200	400,100
Environmental liabilities	17,000	18,000
Customer advances	16,600	16,800
Pension and employee benefit obligations	37,000	44,500
Other	23,400	22,300
Total deferred credits and other liabilities	785,400	789,400
Commitments and contingencies
Capitalization
Long-term debt	807,600	807,500
Common stock — 1,000,000 shares authorized of $100 par value; 933,000 shares outstanding at March 31, 2019 and Dec. 31, 2018, respectively	93,300	93,300
Additional paid in capital	510,100	510,100
Retained earnings	338,600	339,000
Total common stockholder’s equity	942,000	942,400
Total liabilities and equity	$ 2,716,900	$ 2,743,500