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Income Taxes - Consolidated Provision Attributable to Controlling and Non-Controlling Interests (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income tax provision
Current taxes		$ 58.7	$ 129.4	$ 182.0
Deferred taxes		(55.8)	51.9	(123.6)
Income tax expense		$ 2.9	$ 181.3	$ 58.4
Effective tax rate (controlling interest)		(137.00%)	41.00%	6.80%
Controlling interests
Income tax provision
Current taxes		$ 46.5	$ 117.2	$ 173.8
Intangible-related deferred taxes		(51.3)	79.7	(98.5)
Other deferred taxes		(4.3)	(27.5)	(24.9)
Income tax expense		(9.1)	169.4	50.4
Income before income taxes (controlling interest)		$ 6.6	$ 413.0	$ 739.9
Effective tax rate (controlling interest)	[1]	(137.00%)	41.00%	6.80%
Non-Controlling Interests
Income tax provision
Current taxes		$ 12.2	$ 12.2	$ 8.2
Deferred taxes		(0.2)	(0.3)	(0.2)
Income tax expense		$ 12.0	$ 11.9	$ 8.0
[1] Taxes attributable to the controlling interest divided by Income before income taxes (controlling interest).

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- Definition

The component of income tax expense for the period representing the tax effect of the difference between amortization of intangibles for book purposes and amortization of intangibles for tax purposes.

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- Definition

This element represents the income or loss from continuing operations, before income taxes, which is attributable to the controlling interest.

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- Definition

A ratio calculated by dividing the amount of income tax expense attributable to the controlling interest by pretax income from continuing operations attributable to the controlling interest.

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Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of other deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. For example, but not limited to, acquisition-date income tax benefits or expenses recognized from changes in the acquirer's valuation allowance for its previously existing deferred tax assets resulting from a business combination and adjustments to beginning-of-year balance of a valuation allowance because of a change in circumstance causing a change in judgment about the realizability of the related deferred tax asset in future periods.

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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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