BALANCE SHEETS (UNAUDITED) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Current assets
Cash and cash equivalents	$ 2,336	$ 482
Accounts receivable, net	58,950	62,067
Accounts receivable from affiliates	3,131	4,791
Accrued unbilled revenues	106,276	98,892
Inventories	24,481	31,337
Regulatory assets	23,792	24,020
Derivative instruments	7,892	7,892
Deferred income taxes	34,367	27,528
Prepayments and other	22,257	11,387
Total current assets	283,482	268,396
Property, plant and equipment, net	2,931,276	2,861,756
Other assets
Regulatory assets	320,541	324,081
Derivative instruments	46,976	48,949
Other	17,128	14,759
Total other assets	384,645	387,789
Total assets	3,599,403	3,517,941
Current liabilities
Short-term debt	16,000	9,000
Borrowings under utility money pool arrangement	20,000	0
Accounts payable	147,394	141,327
Accounts payable to affiliates	11,117	12,363
Regulatory liabilities	68,123	75,891
Taxes accrued	16,724	19,380
Accrued interest	25,547	15,104
Dividends payable	17,113	16,773
Derivative instruments	3,601	3,601
Other	29,374	31,084
Total current liabilities	354,993	324,523
Deferred credits and other liabilities
Deferred income taxes	680,046	662,201
Regulatory liabilities	88,582	91,815
Asset retirement obligations	17,854	17,607
Derivative instruments	36,890	37,790
Pension and employee benefit obligations	76,505	97,273
Other	3,325	6,093
Total deferred credits and other liabilities	903,202	912,779
Commitments and contingencies
Capitalization
Long-term debt	1,103,740	1,103,684
Common stock - 200 shares authorized of $1.00 par value; 100 shares outstanding at March 31, 2013 and Dec. 31, 2012, respectively	0	0
Additional paid in capital	908,186	843,186
Retained earnings	330,572	335,101
Accumulated other comprehensive loss	(1,290)	(1,332)
Total common stockholder's equity	1,237,468	1,176,955
Total liabilities and equity	$ 3,599,403	$ 3,517,941