Acquisitions Net Assets Acquired (Details) - USD ($)			3 Months Ended	9 Months Ended
	Oct. 16, 2018	May 30, 2018	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019
Business Acquisition [Line Items]
Cash and cash equivalents			$ 18,062,000	$ 18,062,000	$ 7,513,000	$ 11,091,000
Accounts receivable — net			2,146,000	2,146,000	1,631,000
Property, Plant and Equipment, Net			236,418,000	236,418,000	233,554,000
Property, plant and equipment			334,769,000	334,769,000	326,303,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment			(98,351,000)	(98,351,000)	(92,749,000)
Accounts payable			(195,000)	(195,000)	(992,000)
Customer and Meter Deposits			(1,513,000)	(1,513,000)	(1,445,000)
Contributions in Aid of Construction			(14,580,000)	(14,580,000)	(14,520,000)
Business Combination, Contingent Consideration, Liability, Noncurrent			1,773,000	1,773,000	1,773,000
Accrued Liabilities, Current			(8,615,000)	(8,615,000)	(7,546,000)
Goodwill			4,398,000	4,398,000	$ 4,398,000
Red Rock Utilities [Member]
Business Acquisition [Line Items]
Accounts receivable — net			111	111
Property, Plant and Equipment, Net			19,841	19,841
Property, plant and equipment			748	748
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment			(6,084)	(6,084)
Prepaid Expense			12	12
Intangible Assets, Gross (Excluding Goodwill)			196	196
Accounts payable			(26)	(26)
Taxes Payable			(14)	(14)
Accrued Liabilities			(47)	(47)
Customer and Meter Deposits			(76)	(76)
Advances in aid of construction			3,423	3,423
Contributions in Aid of Construction			(7,397)	(7,397)
Business Combination, Contingent Consideration, Liability, Noncurrent			838	838
Assets			3,003	3,003
Goodwill			2,848	2,848
Payments to Acquire Businesses, Gross	$ 5,900,000			5,851
Turner Ranches Water and Sanitation Company [Member]
Business Acquisition [Line Items]
Cash and cash equivalents			176,000	176,000
Accounts receivable — net			121,000	121,000
Property, Plant and Equipment, Net			4,495,000	4,495,000
Property, plant and equipment			92,000	92,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment			(3,554,000)	(3,554,000)
Accounts payable			(30,000)	(30,000)
Accrued Liabilities, Current			(49,000)	(49,000)
Assets			1,251,000	1,251,000
Goodwill			1,549,000	$ 1,549,000
Payments to Acquire Businesses, Gross		$ 2,800,000	$ 2,800,000