CORPORATE BORROWINGS AND FINANCE LEASE LIABILITIES - Long-term debt and lease obligations (Details) £ in Millions, $ in Millions	6 Months Ended	12 Months Ended
Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jun. 30, 2024 GBP (£)
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 4,302.9	$ 4,504.3
Finance lease liabilities	50.6	55.4
Deferred financing costs	(27.5)	(31.1)
Net premium (1)	60.1	104.2
Total carrying value of corporate borrowings and finance lease liabilities	4,386.1	4,632.8
Current maturities of corporate borrowings	(123.1)	(25.1)
Current maturities of finance lease liabilities	(4.3)	(5.4)
Total noncurrent carrying value of corporate borrowings and finance lease liabilities	4,258.7	4,602.3
6.375% Senior Subordinated Notes due 2024
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 5.0	$ 5.1
Stated interest rate (as a percent)	6.375%	6.375%	6.375%
Debt instrument face amount \| £			£ 4.0
5.75 % Senior Subordinated Notes due 2025
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 98.3	$ 98.3
Stated interest rate (as a percent)	5.75%	5.75%	5.75%
5.875% Senior Subordinated Notes due 2026
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 51.5	$ 51.5
Stated interest rate (as a percent)	5.875%	5.875%	5.875%
6.125% Senior Subordinated Notes due 2027
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 125.5	$ 125.5
Stated interest rate (as a percent)	6.125%	6.125%	6.125%
Odeon Senior Secured Note 2027
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Net premium (1)	$ (23.8)	$ (26.4)
Stated interest rate (as a percent)	12.75%	12.75%	12.75%
Senior Secured Credit Facility Term Loan Due 2026
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 1,895.0	$ 1,905.0
Net premium (1)	$ (2.6)	$ (3.3)
Stated interest rate (as a percent)	8.444%	8.474%	8.444%
Odeon Senior Secured Notes Due 2027
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 400.0	$ 400.0
Stated interest rate (as a percent)	12.75%	12.75%	12.75%
First Lien Notes due 2029
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 950.0	$ 950.0
Stated interest rate (as a percent)	7.50%	7.50%	7.50%
Second Lien Subordinated Notes due 2026
CORPORATE BORROWINGS AND FINANCE LEASE OBLIGATIONS
Total principal amount of corporate borrowings	$ 777.6	$ 968.9
Net premium (1)	$ 86.5	$ 133.9
Interest rate cash (as a percent)	10.00%	10.00%
PIK interest rate (as a percent)	12.00%	12.00%

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