Supplemental Financial Information (Other Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Supplemental Financial Information [Abstract]
Unrecognized tax benefits (inclusive of interest and penalties)	$ 313.5	$ 177.0
Liability, Pension and Other Postretirement and Postemployment Benefits, Noncurrent	194.5	0.0
Deferred Tax Liabilities, Net, Noncurrent	88.4	70.7
Intangible Liabilities Noncurrent	52.7	53.5
Long-term lease liability	53.5	0.0
Supplemental executive retirement plan liabilities	25.6	28.1
Deferred tax liabilities	21.0	25.1
Deferred revenue	11.7	20.5
Deferred rent	0.0	11.7
Other	37.3	9.4
Other liabilities	$ 798.2	$ 396.0

For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.

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Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer.

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Amount of obligations incurred for employer-related costs classified as other.

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Amount of liability, recognized in statement of financial position, for pension, other postretirement and postemployment benefits, classified as noncurrent.

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Amount accrued for interest on an underpayment of income taxes and penalties related to a tax position claimed or expected to be claimed in the tax return.

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Intangible Liabilities Noncurrent

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Supplemental Executive Retirement Plan Liabilities

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