BASIS OF PRESENTATION - Liquidity (Details) $ in Thousands, € in Millions, £ in Millions, item in Millions	3 Months Ended						6 Months Ended			12 Months Ended
	Jun. 30, 2022 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($) item	Jun. 30, 2021 USD ($) item	Dec. 31, 2021 USD ($)	Jun. 30, 2023 EUR (€)	Jun. 30, 2022 EUR (€)	Jun. 30, 2022 GBP (£)	Dec. 20, 2021 USD ($)	Dec. 20, 2021 GBP (£)
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Total revenues	$ 1,166,400				$ 444,700			$ 1,952,100	$ 593,000
Number of patrons | item								98.2	28.9
Increase in patrons | item								69.3
Net cash used in operating activities	(76,600)	$ (295,000)	$ 46,500	$ (113,900)	(233,800)	$ (312,900)		$ (371,600)	$ (546,700)	$ (614,100)
Increase (decrease) in net cash used in operating activities	218,400	341,500	160,400	119,900	79,100
Deferred lease amounts	218,900		315,100					218,900		315,100
Net cash provided by (used in) investing activities	(48,000)	(54,900)	(36,900)	(28,800)	13,500	(16,000)		(102,900)	(2,500)	(68,200)
Net cash provided by (used in) financing activities	(59,700)	(76,300)	(27,900)	$ (48,300)	1,212,200	$ 854,700		(136,000)	2,066,900	1,990,700
Capital expenditures	40,400	34,800			$ 17,900			75,200	29,800
Investments in non-consolidated entities, net		27,900						27,900	9,300
Proceeds from disposition of Baltics, net of cash and transaction costs									35,200
Proceeds from disposition of long-term assets		7,200						7,200	1,400
Acquisition of theatre assets	(17,800)							(17,800)
Taxes paid for restricted unit withholdings		52,200						52,200
Cash used to pay for deferred financing costs	1,800	17,700						$ 19,500	$ 19,300
Debt repurchased, percent of par value								69.00%
Percentage of commitment amount							35.00%
Outstanding aggregate principal balance	5,115,500		$ 5,169,100					$ 5,115,500		$ 5,169,100
Proceeds from issuance of Notes		950,000
Net proceeds from the Company's equity issuances	11,400							$ 11,400
Principal and premium repayments	$ 57,900	$ 955,700
Senior Secured Credit Facility
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Amount of minimum liquidity requirements							$ 139,500							$ 139,500
Aggregate principal amount							100,000							100,000
Odean Term Loan Facility
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Aggregate principal amount							39,500				€ 32.5			$ 39,500	£ 32.5
Odeon Term Loan due 2023
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Stated interest rate (as a percent)	11.25%							11.25%				11.25%	11.25%
Outstanding aggregate principal balance												€ 312.2	£ 147.6
Senior Secured Revolving Credit Facility
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Percentage of commitment amount	35.00%
Aggregate principal amount							$ 25,000
First Lien Notes due 2029
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Proceeds from issuance of Notes								$ 950,000
Minimum | Senior Secured Revolving Credit Facility
THE COMPANY AND SIGNIFICANT ACCOUNTING POLICIES
Aggregate principal amount	$ 25,000							$ 25,000