Segment Information (Company's Segment Information, Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Segment Reporting Information [Line Items]
Total assets	$ 13,399,488	$ 9,361,985
Other [Member]
Segment Reporting Information [Line Items]
Total assets	431,428	2,092,581
Regulated [Member] | Water [Member]
Segment Reporting Information [Line Items]
Total assets	7,698,216	$ 7,269,404
Regulated [Member] | Natural Gas [Member]
Segment Reporting Information [Line Items]
Total assets	$ 5,269,844