Business And Significant Accounting Policies (Schedule Of Cash, Cash Equivalents And Restricted Cash) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Business And Significant Accounting Policies [Abstract]
Cash and cash equivalents	$ 104,000	$ 11,000
Restricted cash, current	35,000	13,000
Restricted cash, noncurrent	66,000	30,000
Total cash, cash equivalents and restricted cash on the Statements of Consolidated Cash Flows	$ 205,000	$ 54,000	$ 11,000	$ 27,000