Summary Of Significant Accounting Policies (Utility Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Accounting Policies [Abstract]
Utility-related taxes	$ 12,663	$ 12,095	$ 47,799	$ 43,033
Property taxes	9,991	10,047	29,829	29,757
Other taxes	615	527	2,105	1,879
Utilities Operating Expense, Taxes	$ 23,269	$ 22,669	$ 79,733	$ 74,669

Public Utility Operating Expenses Excise Taxes Collected and Reported Gross in Revenues and Operating Expenses

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- Definition

Public Utility Operating Expenses, Taxes Other than Income, Excise or Property Taxes

+ References

No definition available.

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- Definition

A tax based on the assessed value of real estate by the local government. The tax is usually based on the value of property (including the land).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6419918&loc=d3e35301-107843

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- Definition

Amount of operating expense for taxes other than income taxes of regulated operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2(b))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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