Other Investments- Summary of Transactions with Each of the Company's Other Investees (Detail) (Parenthetical) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)
Digital Cinema Distribution Coalition [Member]
Schedule of Equity Method Investments [Line Items]
Lease Termination Payment	$ 1.0

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.

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