LEASES - Lease costs (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Lessee, Lease, Description [Line Items]
Interest on lease liabilities	$ 1.4	$ 1.5	$ 2.8	$ 3.1
Total lease cost	215.9	232.0	415.4	487.7
Depreciation and amortization
Lessee, Lease, Description [Line Items]
Amortization of finance lease assets	1.3	1.7	2.6	3.6
Finance lease obligations
Lessee, Lease, Description [Line Items]
Interest on lease liabilities	1.4	1.5	2.8	3.1
Theatres \| Rent
Lessee, Lease, Description [Line Items]
Operating lease cost	190.7	203.9	366.2	420.8
Variable lease cost	14.8	20.2	31.4	41.1
Theatres \| Operating expense
Lessee, Lease, Description [Line Items]
Operating lease cost		0.1	0.1	2.3
Operating lease cost	(0.7)
Equipment \| Operating expense
Lessee, Lease, Description [Line Items]
Operating lease cost	2.3	3.8	4.6	7.7
Variable lease cost	4.8		5.0	6.5
Variable lease cost		(0.5)
Office And Other \| General and administrative: other
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 1.3	$ 1.3	$ 2.7	$ 2.6

Amount of other operating lease costs.

No definition available.

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- Definition

Amount of other variable lease costs.

+ References

No definition available.

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- Definition

Amount of interest expense on finance lease liability.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of amortization expense attributable to right-of-use asset from finance lease.

+ References

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- Definition

Amount of lease cost recognized by lessee for lease contract.

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- Definition

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.

+ References

No definition available.

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

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- Definition

Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

+ References

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