Financial Instruments and Hedging Activities (Fair Values of Derivative Instruments Included on Consolidated Balance Sheet) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	$ 272.8	$ 206.3
Liability Derivatives Fair Value	4.3	16.6
Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	64.2	34.7
Liability Derivatives Fair Value	2.2	13.9
Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	208.6	171.6
Liability Derivatives Fair Value	2.1	2.7
Interest Rate Contract [Member] | Accrued Expenses And Other Current Liabilities [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Liability Derivatives Fair Value	0.0	0.1
Interest Rate Contract [Member] | Other Liabilities [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Liability Derivatives Fair Value	0.0	11.8
Interest Rate Contract [Member] | Other Assets [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	22.6	0.0
Equity [Member] | Accrued Expenses And Other Current Liabilities [Member] | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Liability Derivatives Fair Value	1.9	2.7
Equity [Member] | Prepaid Expenses and Other Current Assets [Member] | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	0.0	167.1
Equity [Member] | Other Assets [Member] | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	194.4	0.0
Foreign Exchange [Member] | Accrued Expenses And Other Current Liabilities [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Liability Derivatives Fair Value	0.6	0.7
Foreign Exchange [Member] | Accrued Expenses And Other Current Liabilities [Member] | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Liability Derivatives Fair Value	0.2	0.0
Foreign Exchange [Member] | Prepaid Expenses and Other Current Assets [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	32.7	30.9
Foreign Exchange [Member] | Prepaid Expenses and Other Current Assets [Member] | Derivatives Not Designated as Hedging Instruments
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	14.2	4.5
Foreign Exchange [Member] | Other Liabilities [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Liability Derivatives Fair Value	1.6	1.3
Foreign Exchange [Member] | Other Assets [Member] | Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Asset Derivatives Fair Value	$ 8.9	$ 3.8