Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Commitments And Contingencies [Abstract]
Estimated annual commitments to purchase water through the next five years	$ 5,032
Aggregate amount of the commitments for the remaining years	$ 4,433
Purchase Obligation Term	20 years
Aggregate amount accrued for loss contingencies	$ 19,591
Amount probable of recovery through insurance	7,941
Contingent liability for self-insured employee medical benefit program	$ 1,852	$ 1,515