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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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PROPERTY (Details) - USD ($) $ in Millions	12 Months Ended
PROPERTY (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
PROPERTY
Property owned, gross	$ 4,492.4	$ 4,388.3
Less: accumulated depreciation	2,232.1	1,812.5
Property owned, net	2,260.3	2,575.8
Property leased under finance leases, gross	73.2	81.0
Less: accumulated depreciation and amortization	11.0	7.6
Property leased under finance leases, net	62.2	73.4
Property including property leased under finance leases, net	2,322.5	2,649.2
Depreciation expense	453.2	413.6	$ 498.2
Land
PROPERTY
Property owned, gross	92.6	106.3
Buildings and improvements
PROPERTY
Property owned, gross	$ 222.3	230.4
Buildings and improvements \| Minimum
PROPERTY
Estimated useful lives	1 year
Buildings and improvements \| Maximum
PROPERTY
Estimated useful lives	40 years
Leasehold improvements
PROPERTY
Property owned, gross	$ 1,833.8	1,834.8
Leasehold improvements \| Minimum
PROPERTY
Estimated useful lives	1 year
Leasehold improvements \| Maximum
PROPERTY
Estimated useful lives	20 years
Furniture, fixtures and equipment
PROPERTY
Property owned, gross	$ 2,343.7	$ 2,216.8
Furniture, fixtures and equipment \| Minimum
PROPERTY
Estimated useful lives	1 year
Furniture, fixtures and equipment \| Maximum
PROPERTY
Estimated useful lives	15 years