Cash, Cash Equivalents And Restricted Cash (Reconciliation Of Cash, Cash Equivalents And Restricted Cash) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Cash and cash equivalents	$ 198,122	$ 193,685
Restricted Cash	5,956	8,416
Total cash, cash equivalents and restricted cash	204,078	202,101	$ 106,577	$ 119,863
General Corporate Purposes [Member]
Cash and cash equivalents	80,904	43,760
Joint Venture [Member]
Cash and cash equivalents	$ 117,218	$ 149,925