CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues
Electric	$ 266,629	$ 238,513	$ 756,374	$ 695,921
Gas	34,369	34,226	170,283	193,389
Total Revenues	300,998	272,739	926,657	889,310
Operating Expenses
Cost of sales	96,156	73,577	293,283	265,495
Operating, general and administrative	68,290	79,296	220,730	222,139
Property and other taxes	40,673	35,712	111,302	100,953
Depreciation and depletion	39,763	35,693	119,551	107,239
Total Operating Expenses	244,882	224,278	744,866	695,826
Operating Income	56,116	48,461	181,791	193,484
Interest Expense, net	(21,049)	(22,043)	(71,979)	(68,101)
Other (Loss) Income	(121)	3,769	4,176	5,429
Income Before Income Taxes	34,946	30,187	113,988	130,812
Income Tax Benefit (Expense)	9,659	(6,389)	4,240	(24,616)
Net Income	$ 44,605	$ 23,798	$ 118,228	$ 106,196
Average Common Shares Outstanding	48,314,783	47,065,082	48,288,678	47,028,924
Basic Earnings per Average Common Share	$ 0.92	$ 0.51	$ 2.45	$ 2.26
Diluted Earnings per Average Common Share	0.92	0.51	2.44	2.25
Dividends Declared per Common Share	$ 0.50	$ 0.48	$ 1.50	$ 1.44