Financial Instruments - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) Country	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) Country	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Financial Instruments (Textual) [Abstract]
Significant transfers into/out of Level 3	$ 0	$ 0	$ 0	$ 0
Number of countries that generate box office | Country	82		82
Foreign Exchange contract settlement date range			settlement dates throughout 2020 and 2021
Estimated gains to be reclassified to earnings within the next twelve months			$ 500,000
Investment in equity securities	$ 14,803,000		14,803,000		$ 15,685,000
Investment in equity securities - cost	15,200,000		$ 15,200,000
Equity securities restrictions			lock-up period of six months
Gain (loss) in fair value of investments	1,575,000	$ (490,000)	$ (939,000)	$ (2,543,000)
Maoyan [Member]
Financial Instruments (Textual) [Abstract]
Investment in equity securities	13,700,000		13,700,000		14,600,000
Fixed Income Securities [Member]
Financial Instruments (Textual) [Abstract]
Equity Investment, Debt Securities	1,100,000		1,100,000		1,000,000.0
Preferred Stock [Member] | Other Assets [Member]
Financial Instruments (Textual) [Abstract]
Investment in equity securities	$ 1,000,000.0		$ 1,000,000.0		$ 1,000,000.0
Maximum [Member]
Financial Instruments (Textual) [Abstract]
Equity securities percentage ownership			1.00%