CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]
Operating Revenues	$ 114,846	$ 110,379	$ 102,069
Operating Expenses:
Operations and Maintenance	60,748	60,458	56,634
Depreciation	10,988	10,409	9,746
Other Taxes	12,140	11,865	11,488
Total Operating Expenses	83,876	82,732	77,868
Operating Income	30,970	27,647	24,201
Other Income (Expense):
Allowance for Funds Used During Construction	314	484	821
Other Income	183	517	1,523
Other Expense	(406)	(144)	(195)
Total Other Income, net	91	857	2,149
Interest Charges	5,807	6,725	6,376
Income before Income Taxes	25,254	21,779	19,974
Income Taxes	8,621	7,383	6,527
Net Income	16,633	14,396	13,447
Preferred Stock Dividend Requirements	190	206	206
Earnings Applicable to Common Stock	$ 16,443	$ 14,190	$ 13,241
Earnings per share of Common Stock:
Basic	$ 1.04	$ 0.90	$ 0.85
Diluted	$ 1.03	$ 0.90	$ 0.84
Average Number of Common Shares Outstanding :
Basic	15,868,000	15,733,000	15,615,000
Diluted	16,110,000	15,995,000	15,877,000
Cash Dividends Paid per Common Share (in dollars per share)	$ 0.753	$ 0.743	$ 0.733