Prepaid And Other Assets (Summary Of Prepaid And Other Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Prepaid And Other Assets [Abstract]
Prepaid expenses	$ 1,945	$ 1,946
Prepaid rent	88	162
Prepaid taxes	816	455
Income taxes receivable	2,016	5,572
Deposits	245	245
Investment in marketable securities	25	26
Restricted cash	7	8
Total prepaid and other current assets	5,142	8,414
Straight-line asset	5,920	6,050
Other non-cinema and non-rental real estate assets	1,134	1,134
Investment in Reading International Trust I	838	838
Long-term deposits	12	8
Total other non-current assets	$ 7,904	$ 8,030