CONDENSED STATEMENTS OF INCOME (UNAUDITED) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating Revenues	$ 174,098	$ 179,436
Operating Expenses:
Cost of Sales (Excluding depreciation)	77,602	86,499
Operations	24,051	20,564
Maintenance	3,422	3,192
Depreciation	8,225	7,157
Energy and Other Taxes	3,003	3,169
Total Operating Expenses	116,303	120,581
Operating Income	57,795	58,855
Other Income and Expense	1,450	1,349
Interest Charges	(2,961)	(4,189)
Income Before Income Taxes	56,284	56,015
Income Taxes	(20,771)	(20,977)
Net Income	$ 35,513	$ 35,038