Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

REVENUE RECOGNITION - Disaggregation of revenue (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenues	$ 162.5	$ 119.5	$ 18.9	$ 941.5	$ 1,447.7	$ 1,316.8	$ 1,506.1	$ 1,200.4	$ 1,242.4	$ 5,471.0	$ 5,460.8
Admissions
Disaggregation of Revenue [Line Items]
Revenues									712.1	3,301.3	3,385.0
Food and beverage
Disaggregation of Revenue [Line Items]
Revenues									362.4	1,719.6	1,671.5
Total other theatre
Disaggregation of Revenue [Line Items]
Revenues									167.9	450.1	404.3
Advertising
Disaggregation of Revenue [Line Items]
Revenues									80.5	143.0	142.2
Other theatre
Disaggregation of Revenue [Line Items]
Revenues									87.4	307.1	262.1
Products and services transferred at point in time
Disaggregation of Revenue [Line Items]
Revenues									1,086.0	5,071.0	5,218.7
Products and services transferred over time
Disaggregation of Revenue [Line Items]
Revenues									$ 156.4	$ 400.0	$ 242.1