Description Of Business And Segment Reporting (Summary Of Results Of Operations For Principal Business Segments) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	$ 31,803	$ 10,191	$ 89,142	$ 62,841
Segment operating income (loss)	(10,951)	(17,375)	(37,461)	(46,610)
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	31,803	10,191	89,142	62,841
Segment operating income (loss)	(6,542)	(14,254)	(24,587)	(34,782)
Intersegment Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	(125)	(171)	(386)	(1,953)
Cinema Exhibition [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	28,751	7,339	79,580	54,866
Segment operating income (loss)	(5,057)	(13,410)	(20,680)	(33,318)
Real Estate [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	3,177	3,023	9,948	9,928
Segment operating income (loss)	$ (1,485)	$ (844)	$ (3,907)	$ (1,464)