CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 7,635	$ 21,089
Accounts receivable, net	322,885	328,675
Accounts receivable from affiliates	50,842	19,136
Investments in utility money pool arrangement	16,000	72,000
Accrued unbilled revenues	294,049	270,917
Inventories	238,979	238,007
Regulatory assets	120,120	150,163
Deferred income taxes	64,587	87,267
Derivative instruments	1,731	6,576
Prepaid Taxes	90,365	9,439
Prepayments and other	23,979	23,190
Total current assets	1,231,172	1,226,459
Property, plant and equipment, net	11,626,956	10,742,397
Other assets
Regulatory assets	903,973	826,037
Derivative instruments	5,176	6,905
Other	48,506	52,520
Total other assets	957,655	885,462
Total assets	13,815,783	12,854,318
Current liabilities
Current portion of long-term debt	8,178	282,143
Short-term debt	382,000	0
Accounts payable	425,133	451,243
Accounts payable to affiliates	46,736	45,902
Regulatory liabilities	134,459	79,499
Taxes accrued	159,470	154,194
Accrued interest	48,409	48,492
Dividends payable to parent	83,652	65,134
Derivative instruments	5,774	6,734
Other	72,002	89,571
Total current liabilities	1,365,813	1,222,912
Deferred credits and other liabilities
Deferred income taxes	2,437,641	2,206,179
Deferred investment tax credits	36,273	39,230
Regulatory liabilities	464,421	424,690
Asset retirement obligations	225,296	60,398
Derivative instruments	18,257	23,366
Customer advances	229,990	251,062
Pension and employee benefit obligations	202,031	167,127
Other	68,171	66,855
Total deferred credits and other liabilities	3,682,080	3,238,907
Commitments and contingencies
Capitalization
Long-term debt	3,882,051	3,590,500
Common stock — 100 shares authorized of $0.01 par value; 100 shares outstanding at Dec. 31, 2014 and 2013, respectively	0	0
Additional paid in capital	3,522,788	3,441,290
Retained earnings	1,386,929	1,384,047
Accumulated other comprehensive loss	(23,878)	(23,338)
Total common stockholder’s equity	4,885,839	4,801,999
Total liabilities and equity	$ 13,815,783	$ 12,854,318