Summary of Recognition of Revenue Related To Deferred Revenue (Detail 1) $ in Thousands	Mar. 31, 2021 USD ($)
N C M Screen Advertising Advances
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue remaining performance obligation, amount	$ 342,240	[1]

[1] Amounts are net of the estimated interest to be accrued for the periods presented.  See discussion of significant financing component below.