Statement of Comprehensive Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
OPERATING REVENUES	$ 120,500	$ 120,448
OPERATING EXPENSES:
General and administrative	14,081	13,827
Operation and maintenance	15,452	17,252
Depreciation	25,461	25,315
Regulatory debits	1,247	849
Taxes, other than income taxes	4,781	4,352
Total operating expenses	61,022	61,595
OPERATING INCOME	59,478	58,853
OTHER (INCOME) AND OTHER EXPENSES:
Interest expense	8,362	11,477
Allowance for equity and borrowed funds used during construction	(150)	(383)
Miscellaneous other (income) expenses, net	117	638
Total other (income) and other expenses	8,329	11,732
NET INCOME	51,149	47,121
CASH FLOW HEDGES:
Amortization of cash flow hedges into Interest expense	0	(15)
COMPREHENSIVE INCOME	$ 51,149	$ 47,106