Aquisitions Pro Forma Summary for Prior Year (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating Revenues	$ 19,489,000	$ 24,461,000	$ 21,348,000	$ 18,540,000	$ 15,426,000	$ 20,628,000	$ 17,359,000	$ 15,989,000	$ 83,838,000	$ 69,402,000	$ 66,408,000
Regulated Operating Revenue, Other									1,487,000	1,490,000	1,345,000
Revenues									92,561,000	75,574,000	72,827,000
Net Income	1,593,000	5,974,000	4,163,000	1,910,000	1,828,000	3,734,000	3,470,000	2,268,000	13,640,000	11,300,000	9,798,000
Earnings Per Share, Basic	$ 0.16	$ 0.69	$ 0.48	$ 0.22	$ 0.21	$ 0.43	$ 0.41	$ 0.26	$ 1.55	$ 1.31	$ 1.14
Earnings Per Share, Diluted	$ 0.16	$ 0.67	$ 0.47	$ 0.22	$ 210.00	$ 0.42	$ 0.40	$ 0.26	$ 1.53	$ 1.29	$ 1.13
Maine Water Company Acquisition [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Operating Revenues									11,502,000	84,896,000
Regulated Operating Revenue, Other									0	1,490,000
Real Estate Revenue, Net									0	0
Sales Revenue, Services, Net									717,000	5,382,000
Revenues									12,219,000	91,768,000
Net Income									$ 1,609,000	$ 13,275,000
Earnings Per Share, Basic									$ 0.18	$ 1.54
Earnings Per Share, Diluted									$ 0.18	$ 1.52