Organization, Summary of Significant Accounting Policies and Recent Developments (Schedule of Depreciation Rates) (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Source of Supply [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.15%	1.15%	1.15%
Source of Supply [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.44%	3.44%	3.44%
Pumping [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.00%	2.00%	2.00%
Pumping [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	5.39%	5.39%	5.39%
Water Treatment [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.65%	1.65%	1.65%
Water Treatment [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	7.09%	7.09%	7.09%
General Plant [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.08%	2.08%	2.08%
General Plant [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	17.84%	17.84%	17.84%
Wastewater Collection [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.42%	1.42%	1.42%
Wastewater Collection [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.81%	1.81%	1.81%
T&D Mains [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.10%	1.10%	1.10%
T&D Mains [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.13%	3.13%	3.13%
T&D Services [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	2.12%	2.12%	2.12%
T&D Services [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	3.16%	3.16%	3.16%
T&D Other [Member] | Minimum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	1.61%	1.61%	1.61%
T&D Other [Member] | Maximum [Member]
Public Utility, Property, Plant and Equipment [Line Items]
Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service	4.63%	4.63%	4.63%