Represents the amount of Adjusted Earnings Before Interest, Taxes, Depreciation, and Amortization.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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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.

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OPERATING SEGMENTS (Details) $ in Millions	3 Months Ended
OPERATING SEGMENTS (Details) $ in Millions	Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)	Aug. 28, 2020
OPERATING SEGMENT
Number of reportable segments \| segment	2
Interest in non-consolidated affiliates (as a percent)	49.00%
Financial information by reportable operating segment
Revenues	$ 148.3	$ 941.5
Adjusted EBITDA	294.7	(3.1)
Capital expenditures	11.9	91.7
Long-term assets, net	$ 9,472.7		$ 9,789.4
Forum Cinemas OU [Member]
OPERATING SEGMENT
Interest in non-consolidated affiliates (as a percent)				49.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] \| Forum Cinemas OU [Member]
OPERATING SEGMENT
Interest in non-consolidated affiliates (as a percent)	51.00%
U. S. markets \| Operating Segments [Member]
Financial information by reportable operating segment
Revenues	$ 137.2	661.3
Adjusted EBITDA	200.4	3.8
Capital expenditures	6.6	56.9
Long-term assets, net	6,727.9		6,895.3
International markets \| Operating Segments [Member]
Financial information by reportable operating segment
Revenues	11.1	280.2
Adjusted EBITDA	94.3	(6.9)
Capital expenditures	5.3	$ 34.8
Long-term assets, net	$ 2,744.8		$ 2,894.1