INCOME TAXES (Components Of The Net Deferred Tax Asset And Related Valuation Allowance) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Assets:
Operating lease liability	$ 878.5
Net operating loss carryforwards	356.6	$ 264.9
Accrued asset retirement obligations	174.9	165.7
Stock-based compensation	5.6	6.3
Unearned revenue	31.7	28.3
Unrealized loss on foreign currency	3.8	12.9
Other accruals and allowances	65.6	78.6
Items not currently deductible and other	26.1	26.2
Liabilities:
Depreciation and amortization	(1,040.3)	(757.0)
Right-of-use asset	(865.1)
Deferred rent	(79.7)	(36.9)
Other	0.0	(15.3)
Subtotal	(442.3)	(226.3)
Valuation allowance	(194.2)	(151.9)	$ (142.0)	$ (144.4)
Net deferred tax liabilities	$ (636.5)	$ (378.2)

Deferred Tax Assets, Operating Lease Liability

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Deferred Tax Liabilities (Assets), Gross

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Net Long Term Operating Loss Carry Forwards

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from deferred income.

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