Other Investments- Summary of Transactions with Each of the Company's Other Investees (Detail) (Parenthetical) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2021
Digital Cinema Distribution Coalition [Member]
Schedule of Equity Method Investments [Line Items]
Lease Termination Payment	$ 1.0	$ 2.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_ScheduleOfEquityMethodInvestmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration