v3.21.1
LEASES - Lease costs (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Lessee, Lease, Description [Line Items]    
Interest on lease liabilities $ 1.4 $ 1.6
Total lease cost 199.5 255.7
Depreciation and amortization    
Lessee, Lease, Description [Line Items]    
Amortization of finance lease assets 1.3 1.9
Finance lease obligations    
Lessee, Lease, Description [Line Items]    
Interest on lease liabilities 1.4 1.6
Theatres | Rent    
Lessee, Lease, Description [Line Items]    
Operating lease cost 175.5 216.9
Variable lease cost 16.6 20.9
Theatres | Operating expense    
Lessee, Lease, Description [Line Items]    
Operating lease cost 0.8 2.2
Equipment | Operating expense    
Lessee, Lease, Description [Line Items]    
Operating lease cost 2.3 3.9
Variable lease cost   7.0
Variable lease cost 0.2  
Office And Other | General and administrative: other    
Lessee, Lease, Description [Line Items]    
Operating lease cost $ 1.4 $ 1.3