Debt (Summary Of Notes Payable) (Details) - USD ($) $ in Thousands					9 Months Ended		12 Months Ended
		Dec. 29, 2016	Dec. 13, 2016	Mar. 03, 2016	Sep. 30, 2017		Dec. 31, 2016
Debt Instrument [Line Items]
Contractual facility					$ 272,717		$ 266,134
Balance Gross					151,312		148,535
Balance Net					147,524	[1]	143,614	[2]
Deferred financing costs, net					$ 3,800		$ 4,900
Trust Preferred Securities [Member]
Debt Instrument [Line Items]
Maturity date					Apr. 30, 2027		Apr. 30, 2027
Contractual facility					$ 27,913		$ 27,913
Balance Gross					27,913		27,913
Balance Net					$ 27,501	[1]	$ 27,340	[2]
Stated interest rate					5.31%		4.89%
Effective interest rate					5.20%	[3]	5.20%	[4]
US Bank Of America Credit Facility [Member]
Debt Instrument [Line Items]
Maturity date					Nov. 28, 2019		Nov. 28, 2019
Contractual facility				$ 55,000	$ 55,000		$ 55,000
Balance Gross					40,500		39,950
Balance Net					$ 40,481	[1]	$ 39,759	[2]
Stated interest rate					3.74%		3.27%
Effective interest rate					3.65%	[3]	3.90%	[4]
US Bank Of America Line Of Credit [Member]
Debt Instrument [Line Items]
Maturity date					Oct. 31, 2019		Oct. 31, 2019
Contractual facility					$ 5,000		$ 5,000
Stated interest rate					4.24%		3.77%
Effective interest rate					4.24%	[3]	3.77%	[4]
US Cinema 1, 2, 3 Term Loan [Member]
Debt Instrument [Line Items]
Maturity date					Sep. 01, 2019	[5]	Sep. 01, 2019	[6]
Contractual facility					$ 19,601	[5]	$ 19,901	[6]
Balance Gross					19,601	[5]	19,901	[6]
Balance Net					$ 19,168	[1],[5]	$ 19,356	[2],[6]
Stated interest rate					3.25%	[5]	3.25%	[6]
Effective interest rate					3.25%	[3],[5]	3.25%	[4],[6]
Minetta and Orpheum Theatres Loan [Member]
Debt Instrument [Line Items]
Maturity date					Jun. 01, 2018	[5]	Jun. 01, 2018	[6]
Contractual facility					$ 7,500	[5]	$ 7,500	[6]
Balance Gross					7,500	[5]	7,500	[6]
Balance Net					$ 7,452	[1],[5]	$ 7,398	[2],[6]
Stated interest rate					4.00%	[5]	3.38%	[6]
Effective interest rate					4.00%	[3],[5]	3.38%	[4],[6]
U.S. Corporate Office Term Loan [Member]
Debt Instrument [Line Items]
Maturity date					Jan. 01, 2027	[5]	Jan. 01, 2027	[6]
Contractual facility			$ 8,400		$ 9,774	[5]	$ 8,363	[6]
Balance Gross					9,774	[5]	8,363	[6]
Balance Net					$ 9,651	[1],[5]	$ 8,239	[2],[6]
Stated interest rate					4.64%	[5]	4.64%	[6]
Effective interest rate					4.64%	[3],[5]	4.64%	[4],[6]
US Union Square Construction Financing [Member]
Debt Instrument [Line Items]
Maturity date					Dec. 29, 2019	[5]	Dec. 29, 2019	[6]
Contractual facility		$ 57,500			$ 57,500	[5]	$ 57,500	[6]
Balance Gross					8,000	[5]	8,000	[6]
Balance Net					$ 5,351	[1],[5]	$ 4,751	[2],[6]
Stated interest rate					5.49%	[5]	4.52%	[6]
Effective interest rate					5.49%	[3],[5]	4.52%	[4],[6]
NAB Corporate Term Loan [Member]
Debt Instrument [Line Items]
Maturity date					Jun. 28, 2019	[7]	Jun. 30, 2019	[8]
Contractual facility					$ 52,136	[7]	$ 48,080	[8]
Balance Gross					38,024	[7]	28,558	[8]
Balance Net					$ 37,920	[1],[7]	$ 28,421	[2],[8]
Stated interest rate					3.55%	[7]	2.64%	[8]
Effective interest rate					3.55%	[3],[7]	2.64%	[4],[8]
Westpac Bank Corporate Credit Facility [Member]
Debt Instrument [Line Items]
Maturity date					Dec. 31, 2018	[7]	Mar. 31, 2018	[8]
Contractual facility					$ 38,293	[7]	$ 36,877	[8]
Balance Gross	[8]						8,350
Balance Net	[2],[8]						$ 8,350
Stated interest rate					3.70%	[7]	3.80%	[8]
Effective interest rate					3.70%	[3],[7]	3.80%	[4],[8]

[1] Net of deferred financing costs amounting to $3.8 million.

[2] Net of deferred financing costs amounting to $4.9 million.

[3] Effective interest rate includes the impact of interest rate derivatives hedging the interest rate risk associated with Trust Preferred Securities and Bank of America Credit Facility that were outstanding as of September 30, 2017.

[4] Effective interest rate includes the impact of interest rate derivatives hedging the interest rate risk associated with Trust Preferred Securities and Bank of America Credit Facility that were outstanding as of December 31, 2016.

[5] The loan for our Minetta & Orpheum Theatres was obtained from Santander Bank. The term loan for our Cinema 1,2,3 Theatre was refinanced during the third quarter of 2016 with Valley National Bank. The term loan, which is collateralized by our new U.S Corporate Headquarters office building, was obtained with Citizens Asset Finance, Inc. In December 2016, we completed the negotiation of the construction financing for our Union Square redevelopment project, $8.0 million of which was advanced from the total construction loan limit of $57.5 million.

[6] The loan for our Minetta & Orpheum Theatres was obtained from Santander Bank. The term loan for our Cinema 1,2,3 Theatre was refinanced during the third quarter of 2016 with Valley National Bank. The term loan, which is collateralized by our new U.S Corporate Headquarters office building, was obtained with Citizens Asset Finance, Inc.. In December 2016, we completed the negotiation of the construction financing for our Union Square redevelopment project, $8.0 million of which was advanced from the total construction loan limit of $57.5 million. The Minetta & Orpheum Theatres Loan will become due within one year. Currently, we are negotiating with our lender to renew this borrowing. Our loan arrangements are presented, net of the deferred financing costs, on the face of our consolidated balance sheet as follows:Dollars in thousandsBalance Sheet CaptionSeptember 30, 2017December 31, 2016Debt - current portion$ 8,084$ 567 Debt - long-term portion 111,939 115,707 Subordinated debt 27,501 27,340 Total borrowings $ 147,524$ 143,614

[7] The contractual facilities and outstanding balances of the FC-denominated borrowings were translated into U.S. dollars based on the applicable exchange rates as of September 30, 2017.

[8] The contractual facilities and outstanding balances of the FC-denominated borrowings were translated into U.S. dollars based on the applicable exchange rates as of December 31, 2016.