Supplemental Information to Condensed Consolidated Statements of Cash Flows (Parenthetical) (Detail) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2020	Dec. 31, 2019
Supplemental Cash Flow Elements [Abstract]
Additions to theatre properties and equipment included in accounts payable	$ 7,058	$ 14,991

Future cash outflow to pay for purchases of fixed assets that have occurred.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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