Prepaid And Other Assets (Summary Of Prepaid And Other Assets) (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2009	Feb. 05, 2007
Prepaid And Other Assets [Abstract]
Prepaid expenses	$ 1,946,000	$ 2,163,000
Prepaid taxes	455,000	912,000
Income taxes receivable	5,572,000	1,669,000
Prepaid rent	162,000	1,093,000
Deposits	245,000	214,000
Restricted cash	8,000	7,000
Investment in marketable securities	26,000	47,000
Total prepaid and other current assets	8,414,000	6,105,000
Other non-cinema and non-rental real estate assets	1,134,000	1,134,000
Investment in Reading International Trust I	838,000	838,000	$ 838,000	$ 1,500,000
Straight-line rent	6,050,000	4,689,000
Long-term deposits	8,000	7,000
Total non-current assets	$ 8,030,000	$ 6,668,000