Effective Income Tax Rate Reconciliation, Foreign Permanent Differences, Amount

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to foreign income tax expense (benefit).

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to noncontrolling interest income (loss) exempt from income taxes.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to state and local income tax expense (benefit).

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INCOME TAXES - Reconciliation of the Statutory Federal Income Tax Rate (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Statutory rate									21.00%
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Tax computed at the statutory rate									$ 76.1	$ 56.7	$ 42.6
TCJA federal rate change									0.0	0.0	(44.8)
Tax deduction in excess of book compensation from restricted stock vesting									0.3	1.8	(3.7)
Domestic permanent differences, primarily disallowed executive compensation									6.1	3.8	1.3
Foreign permanent differences, primarily non-deductible depreciation, amortization and interest expenses in the United Kingdom									1.3	1.4	6.1
Effect of foreign tax operations on U.S. taxes, net of foreign tax credits and valuation allowance									(16.8)	1.1	1.6
Noncontrolling interests									(22.2)	(15.1)	(15.0)
State income taxes, net of federal benefit									0.0	8.0	(3.8)
Other									(3.4)	0.3	(0.6)
Provision for (benefit from) income taxes	$ 6.3	$ 10.2	$ 20.9	$ 4.0	$ 24.3	$ 6.9	$ 29.4	$ (2.6)	$ 41.4	$ 58.0	$ (16.3)