CONDENSED CONSOLIDATED STATEMENTS OF INCOME - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenues
Electric	$ 244,155	$ 241,237	$ 706,718	$ 733,933
Gas	36,455	33,599	178,507	195,842
Total Revenues	280,610	274,836	885,225	929,775
Operating Expenses
Cost of revenue	68,038	64,227	220,353	235,706
Operating, general and administrative	73,322	76,998	224,042	238,916
Property and other taxes	45,306	44,089	136,786	133,188
Depreciation and depletion	44,289	43,166	134,336	129,766
Total Operating Expenses	230,955	228,480	715,517	737,576
Operating Income	49,655	46,356	169,708	192,199
Interest Expense, net	(23,677)	(23,722)	(72,298)	(71,023)
Other Income (Expense), net	785	(409)	(973)	864
Income Before Income Taxes	26,763	22,225	96,437	122,040
Income Tax Benefit (Expense)	2,703	(555)	5,227	20,098
Net Income	$ 29,466	$ 21,670	$ 101,664	$ 142,138
Average Common Shares Outstanding	50,576,564	50,443,866	50,551,121	50,422,028
Basic Earnings per Average Common Share	$ 0.58	$ 0.43	$ 2.01	$ 2.82
Diluted Earnings per Average Common Share	0.58	0.42	2.01	2.80
Dividends Declared per Common Share	$ 0.600	$ 0.575	$ 1.80	$ 1.725