Goodwill (Schedule Of Goodwill) (Details) $ in Thousands	9 Months Ended
Sep. 30, 2021 USD ($)
Goodwill [Line Items]
Balance	$ 2,324,547
Goodwill acquired
Measurement period purchase price allocation adjustments	16,400
Reclassification to utility plant acquisition adjustment	(111)
Balance	2,340,836
Water [Member] \| Regulated [Member]
Goodwill [Line Items]
Balance	58,659
Reclassification to utility plant acquisition adjustment	(111)
Balance	58,548
Natural Gas [Member] \| Regulated [Member]
Goodwill [Line Items]
Balance	2,261,047
Measurement period purchase price allocation adjustments	16,400
Balance	2,277,447
Other [Member]
Goodwill [Line Items]
Balance	4,841
Goodwill acquired
Measurement period purchase price allocation adjustments
Reclassification to utility plant acquisition adjustment
Balance	$ 4,841

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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