Summary Financial Information for DCIP (Detail) - USD ($) $ in Thousands	3 Months Ended												12 Months Ended
	Dec. 31, 2020		Sep. 30, 2020	[1]	Jun. 30, 2020	[1]	Mar. 31, 2020	[1]	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Equity Method Investments [Line Items]
Total revenues	$ 98,242	[1]	$ 35,478		$ 8,974		$ 543,616		$ 788,803	$ 821,817	$ 957,756	$ 714,723	$ 686,310	[1]	$ 3,283,099	$ 3,221,735
Net income (loss)	(239,674)	[1]	$ (148,036)		$ (170,816)		$ (59,422)		26,839	$ 31,955	$ 101,861	$ 33,193	(617,948)	[1]	193,848	215,305
Current assets	892,747								634,990				892,747		634,990
Current liabilities	606,441								708,800				606,441		708,800
Noncurrent liabilities	4,157,512								3,670,895				4,157,512		3,670,895
Members' equity (deficit)	798,969								1,448,322				798,969		1,448,322	1,408,570	$ 1,405,688
Other Affiliates | Digital Cinema Implementation Partners
Schedule Of Equity Method Investments [Line Items]
Total revenues													30,561		171,531	172,534
Operating income (loss)													(105,691)		99,812	102,236
Net income (loss)													(114,243)		95,820	$ 94,757
Current assets	36,372								51,382				36,372		51,382
Noncurrent assets	205								581,547				205		581,547
Current liabilities	39,844								70,515				39,844		70,515
Noncurrent liabilities	687								190				687		190
Members' equity (deficit)	$ (3,954)								$ 562,224				$ (3,954)		$ 562,224

[1] Quarterly results during the year ended December 31, 2020 were impacted by the COVID-19 pandemic (see Note 3) as well as impairment recorded (see Notes 1 and 11).