CONSOLIDATED BALANCE SHEETS (UNAUDITED) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Current assets
Cash and cash equivalents	$ 34,709	$ 7,635
Accounts receivable, net	256,571	322,885
Accounts receivable from affiliates	11,592	50,842
Investments in utility money pool arrangement	0	16,000
Accrued unbilled revenues	201,230	294,049
Inventories	237,764	238,979
Regulatory assets	88,275	120,120
Deferred income taxes	95,539	64,587
Derivative instruments	1,715	1,731
Prepaid taxes	17,354	90,365
Prepayments and other	21,502	23,979
Total current assets	966,251	1,231,172
Property, plant and equipment, net	11,966,302	11,626,956
Other assets
Regulatory assets	886,072	903,973
Derivative instruments	3,890	5,176
Other	46,864	48,506
Total other assets	936,826	957,655
Total assets	13,869,379	13,815,783
Current liabilities
Current portion of long-term debt	8,921	8,178
Short-term Debt	0	382,000
Accounts payable	325,178	425,133
Accounts payable to affiliates	33,430	46,736
Regulatory liabilities	152,901	134,459
Taxes accrued	132,251	159,470
Accrued interest	27,043	48,409
Dividends payable to parent	83,672	83,652
Derivative instruments	6,437	5,774
Other	80,419	72,002
Total current liabilities	850,252	1,365,813
Deferred credits and other liabilities
Deferred income taxes	2,658,792	2,437,641
Deferred investment tax credits	34,072	36,273
Regulatory liabilities	450,014	464,421
Asset retirement obligations	239,643	225,296
Derivative instruments	14,317	18,257
Customer advances	199,799	229,990
Pension and employee benefit obligations	179,276	202,031
Other	67,871	68,171
Total deferred credits and other liabilities	$ 3,843,784	$ 3,682,080
Commitments and contingencies
Capitalization
Long-term debt	$ 4,125,159	$ 3,882,051
Common stock — 100 shares authorized at $0.01 par value; 100 shares outstanding at Sept. 30, 2015 and Dec. 31, 2014, respectively	0	0
Additional paid in capital	3,551,986	3,522,788
Retained earnings	1,522,282	1,386,929
Accumulated other comprehensive loss	(24,084)	(23,878)
Total common stockholder’s equity	5,050,184	4,885,839
Total liabilities and equity	$ 13,869,379	$ 13,815,783