Summary Financial Information for DCIP (Detail) - Other Affiliates - Digital Cinema Implementation Partners - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Schedule Of Equity Method Investments [Line Items]
Gross revenues	$ 42,521	$ 47,095	$ 83,554	$ 92,574
Operating income	25,049	29,393	48,494	57,872
Net income	22,169	$ 25,616	43,703	$ 49,757
Current assets	51,546		51,546		$ 56,296
Noncurrent assets	725,399		725,399		772,438
Current liabilities	63,982		63,982		59,153
Noncurrent liabilities	213,795		213,795		296,889
Members' equity	$ 499,168		$ 499,168		$ 472,692