Description Of Business And Segment Reporting (Summary Of Results Of Operations For Principal Business Segments) (Details)	12 Months Ended
	Dec. 31, 2021 USD ($) segment	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	$ 139,060,000	$ 77,862,000	$ 276,768,000
Depreciation and amortization	(22,746,000)	(22,317,000)	(22,747,000)
General and administrative expense	(25,100,000)	(16,998,000)	(25,395,000)
Impairment of long-lived assets	0	(217,000)	0
Total costs and expenses	(180,853,000)	(139,175,000)	(267,645,000)
Segment operating income (loss)	$ (41,793,000)	(61,313,000)	9,123,000
Number of operating segments | segment	2
Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	$ 139,575,000	79,977,000	284,094,000
Costs and expenses	(133,522,000)	(101,758,000)	(226,829,000)
Depreciation and amortization	(21,514,000)	(21,347,000)	(22,333,000)
Total costs and expenses	(163,567,000)	(127,496,000)	(255,624,000)
Segment operating income (loss)	(23,992,000)	(47,519,000)	28,470,000
Intersegment Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	(515,000)	(2,115,000)	(7,326,000)
Costs and expenses	(515,000)	(2,115,000)	(7,326,000)
Cinema Exhibition [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Impairment of long-lived assets		(217,000)
Cinema Exhibition [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	126,812,000	67,014,000	262,189,000
Costs and expenses	(123,416,000)	(93,180,000)	(217,376,000)
Depreciation and amortization	(14,422,000)	(15,246,000)	(16,940,000)
Total costs and expenses	(145,449,000)	(112,070,000)	(238,860,000)
Segment operating income (loss)	(18,637,000)	(45,056,000)	23,329,000
Cinema Exhibition [Member] | Intersegment Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Costs and expenses	(515,000)	(2,115,000)	(7,326,000)
Real Estate [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	12,763,000	12,963,000	21,905,000
Costs and expenses	(10,106,000)	(8,578,000)	(9,453,000)
Depreciation and amortization	(7,092,000)	(6,101,000)	(5,393,000)
Total costs and expenses	(18,118,000)	(15,426,000)	(16,764,000)
Segment operating income (loss)	(5,355,000)	(2,463,000)	5,141,000
Real Estate [Member] | Intersegment Eliminations [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	(515,000)	(2,115,000)	(7,326,000)
Segment [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
General and administrative expense	(8,531,000)	(4,174,000)	(6,462,000)
Segment [Member] | Cinema Exhibition [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
General and administrative expense	(7,611,000)	(3,427,000)	(4,544,000)
Segment [Member] | Real Estate [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
General and administrative expense	(920,000)	(747,000)	(1,918,000)
Third Party [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	139,060,000	77,862,000	276,768,000
Costs and expenses	(133,007,000)	(99,643,000)	(219,503,000)
Third Party [Member] | Cinema Exhibition [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	126,812,000	67,014,000	262,189,000
Costs and expenses	(122,901,000)	(91,065,000)	(210,050,000)
Third Party [Member] | Real Estate [Member] | Operating Segments [Member]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Revenue	12,248,000	10,848,000	14,579,000
Costs and expenses	$ (10,106,000)	$ (8,578,000)	$ (9,453,000)