CONDENSED CONSOLIDATED STATEMENTS OF INCOME (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Income Statement [Abstract]
Operating Revenues	$ 31,285	$ 32,353	$ 87,424	$ 83,300
Operating Expenses:
Operations and Maintenance	15,120	15,600	45,698	44,740
Depreciation	2,772	2,629	8,205	7,759
Other Taxes	3,123	3,281	9,215	8,871
Total Operating Expenses	21,015	21,510	63,118	61,370
Operating Income	10,270	10,843	24,306	21,930
Other Income (Expense):
Allowance for Funds Used During Construction	104	110	230	383
Other Income	27	106	124	423
Other Expense	(1)	(4)	(21)	(155)
Total Other Income, net	130	212	333	651
Interest Charges	1,541	1,808	4,234	4,941
Income before Income Taxes	8,859	9,247	20,405	17,640
Income Taxes	3,052	3,109	6,940	5,970
Net Income	5,807	6,138	13,465	11,670
Preferred Stock Dividend Requirements	44	52	147	155
Earnings Applicable to Common Stock	$ 5,763	$ 6,086	$ 13,318	$ 11,515
Earnings per share of Common Stock:
Basic	$ 0.36	$ 0.39	$ 0.84	$ 0.73
Diluted	$ 0.36	$ 0.38	$ 0.83	$ 0.73
Average Number of Common Shares Outstanding :
Basic	15,882,000	15,741,000	15,839,000	15,717,000
Diluted	16,117,000	16,004,000	16,093,000	15,980,000
Cash Dividends Paid per Common Share (in dollars per share)	$ 0.1875	$ 0.185	$ 0.5625	$ 0.555