BALANCE SHEETS (UNAUDITED) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 555	$ 596
Accounts receivable, net	78,710	71,626
Accounts receivable from affiliates	7,618	1,983
Accrued unbilled revenues	102,381	129,287
Inventories	31,749	43,231
Regulatory assets	48,911	52,006
Derivative instruments	14,350	23,776
Deferred income taxes	79,013	51,854
Prepayments and other	45,554	31,476
Total current assets	408,841	405,835
Property, plant and equipment, net	3,831,044	3,743,141
Other assets
Regulatory assets	314,557	323,305
Derivative instruments	31,191	33,164
Other	15,438	15,859
Total other assets	361,186	372,328
Total assets	4,601,071	4,521,304
Current liabilities
Short-term debt	123,000	37,000
Borrowings under utility money pool arrangement	0	16,000
Accounts payable	140,907	160,762
Accounts payable to affiliates	15,343	19,790
Regulatory liabilities	104,009	87,723
Taxes accrued	19,848	27,208
Accrued interest	27,327	17,057
Dividends payable	25,339	27,828
Derivative instruments	3,565	3,565
Other	88,724	80,211
Total current liabilities	548,062	477,144
Deferred credits and other liabilities
Deferred income taxes	878,653	849,145
Regulatory liabilities	110,867	115,188
Asset retirement obligations	26,369	26,031
Derivative instruments	29,752	30,643
Pension and employee benefit obligations	92,647	103,670
Other	9,553	9,320
Total deferred credits and other liabilities	1,147,841	1,133,997
Commitments and contingencies
Capitalization
Long-term debt	1,349,774	1,349,691
Common stock — 200 shares authorized of $1.00 par value; 100 shares outstanding at March 31, 2015 and Dec. 31, 2014, respectively	0	0
Additional paid in capital	1,165,435	1,165,463
Retained earnings	390,906	395,998
Accumulated other comprehensive loss	(947)	(989)
Total common stockholder's equity	1,555,394	1,560,472
Total liabilities and equity	$ 4,601,071	$ 4,521,304