Segment Reporting Segment Reporting (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting Information [Line Items]
Revenues	$ 92,561	$ 75,574	$ 72,827
Depreciation, Depletion and Amortization	9,789	7,780	7,095
Operating Expenses	51,711	42,225	43,919
Other Income (Deductions)	(1,760)	(1,148)	(525)
Interest Expense (Net of AFUDC)	8,330	5,445	5,625
Income Tax Expense (Benefit), Continuing Operations	7,331	7,676	5,865
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	13,640	11,300	9,798
Water Activities [Member]
Segment Reporting Information [Line Items]
Revenues	85,325	70,892	67,753
Depreciation, Depletion and Amortization	9,782	7,773	7,088
Operating Expenses	48,153	39,211	40,301
Other Income (Deductions)	(1,760)	(1,148)	(525)
Interest Expense (Net of AFUDC)	8,343	5,486	5,682
Income Tax Expense (Benefit), Continuing Operations	6,022	7,151	5,488
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	11,265	10,123	8,669
Real Estate Transactions [Member]
Segment Reporting Information [Line Items]
Revenues	1,450	0	0
Depreciation, Depletion and Amortization	0	0	0
Operating Expenses	119	0	0
Other Income (Deductions)	0	0	0
Interest Expense (Net of AFUDC)	0	0	0
Income Tax Expense (Benefit), Continuing Operations	380	(176)	(230)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	951	176	230
Services and Rentals [Member]
Segment Reporting Information [Line Items]
Revenues	5,786	4,682	5,074
Depreciation, Depletion and Amortization	7	7	7
Operating Expenses	3,439	3,014	3,618
Other Income (Deductions)	0	0	0
Interest Expense (Net of AFUDC)	(13)	(41)	(57)
Income Tax Expense (Benefit), Continuing Operations	929	701	607
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 1,424	$ 1,001	$ 899