Revenue Recognition (Schedule Of Disaggregation Of Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Disaggregation of Revenue [Line Items]
Revenue	$ 435,255	$ 411,255	$ 1,481,730	$ 1,574,405
Regulated Water [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	279,241	258,367	757,420	717,819
Revenue	280,023	258,801	759,882	719,422
Regulated Water [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	182,616	173,331	499,859	487,704
Regulated Water [Member] \| Commercial [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	52,577	49,699	140,110	137,427
Regulated Water [Member] \| Fire Protection [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	10,670	10,350	31,793	30,794
Regulated Water [Member] \| Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9,747	9,438	26,527	25,584
Regulated Water [Member] \| Other Water [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	23,631	15,549	59,131	36,310
Regulated Water [Member] \| Alternative Revenue Program [Member]
Disaggregation of Revenue [Line Items]
Revenue	782	434	2,462	1,603
Wastewater [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	51,722	48,819	148,651	140,153
Revenue	51,777	48,892	148,579	140,435
Wastewater [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	37,450	36,096	109,097	103,632
Wastewater [Member] \| Commercial [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9,779	9,396	27,569	26,643
Wastewater [Member] \| Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	1,043	500	2,149	1,587
Wastewater [Member] \| Other Wastewater [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	3,450	2,827	9,836	8,291
Wastewater [Member] \| Alternative Revenue Program [Member]
Disaggregation of Revenue [Line Items]
Revenue	55	73	(72)	282
Regulated Natural Gas [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	96,374	94,798	547,757	673,655
Revenue	96,731	94,798	549,250	675,076
Regulated Natural Gas [Member] \| Residential [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	49,398	46,501	326,921	415,207
Regulated Natural Gas [Member] \| Commercial [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9,838	9,577	66,417	91,031
Regulated Natural Gas [Member] \| Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	228	353	1,475	2,613
Regulated Natural Gas [Member] \| Gas Transportation [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	27,576	26,636	133,458	129,151
Regulated Natural Gas [Member] \| Other Utility [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	9,334	11,731	19,486	35,653
Regulated Natural Gas [Member] \| Alternative Revenue Program [Member]
Disaggregation of Revenue [Line Items]
Revenue	357		1,493	1,421
Other [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,677	2,898	8,389	11,706
Revenue	6,724	8,764	24,019	39,472
Other [Member] \| Other Utility [Member]
Disaggregation of Revenue [Line Items]
Revenues from contracts with customers	2,677	2,898	8,389	11,706
Other [Member] \| Other And Eliminations [Member]
Disaggregation of Revenue [Line Items]
Revenue	$ 4,047	$ 5,866	$ 15,630	$ 27,766