Consolidated Statements of Income (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Operating Revenues
Electric	$ 102,231	$ 97,918	$ 220,774	$ 210,903
Product Sales	109,855	105,564	205,429	198,821
Total Operating Revenues	212,086	203,482	426,203	409,724
Operating Expenses
Production Fuel – Electric	12,477	9,990	28,859	25,690
Purchased Power – Electric System Use	16,376	15,127	35,564	32,013
Electric Operation and Maintenance Expenses	37,850	38,981	76,229	78,999
Cost of Products Sold (depreciation included below)	84,013	80,949	159,290	153,588
Other Nonelectric Expenses	10,164	9,238	20,602	20,693
Depreciation and Amortization	17,908	18,525	35,762	36,814
Property Taxes – Electric	3,709	3,589	7,507	7,268
Total Operating Expenses	182,497	176,399	363,813	355,065
Operating Income	29,589	27,083	62,390	54,659
Interest Charges	7,527	7,976	14,989	15,970
Other Income	552	1,532	1,105	1,932
Income Before Income Taxes—Continuing Operations	22,614	20,639	48,506	40,621
Income Tax Expense—Continuing Operations	5,897	5,083	12,260	10,575
Net Income from Continuing Operations	16,717	15,556	36,246	30,046
Discontinued Operations
Income – net of Income Tax Expense of $40, $80, $78 and $100 for the respective periods	61	119	117	149
Net Income	$ 16,778	$ 15,675	$ 36,363	$ 30,195
Average Number of Common Shares Outstanding—Basic (in shares)	39,462,865	38,179,371	39,406,834	38,058,157
Average Number of Common Shares Outstanding—Diluted (in shares)	39,702,499	38,321,289	39,671,612	38,183,249
Basic Earnings Per Common Share:
Continuing Operations (in dollars per share)	$ 0.43	$ 0.41	$ 0.92	$ 0.79
Discontinued Operations (in dollars per share)
(in dollars per share)	0.43	0.41	0.92	0.79
Diluted Earnings Per Common Share:
Continuing Operations (in dollars per share)	0.42	0.41	0.92	0.79
Discontinued Operations (in dollars per share)
(in dollars per share)	0.42	0.41	0.92	0.79
Dividends Declared Per Common Share (in dollars per share)	$ 0.32	$ 0.3125	$ 0.64	$ 0.625