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Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	Jan. 01, 2018
Income Tax Contingency [Line Items]
Statutory rate	21.00%		35.00%	21.00%	35.00%
Income tax expense	$ 369.8		$ 383.8	$ 956.0	$ 892.6
2017 Tax Act
Income Tax Contingency [Line Items]
Statutory rate				21.00%		35.00%
Income tax expense		$ 1,200.0
Transition toll tax liabilities	34.6	989.6		$ 34.6		$ 989.6
Remeasurement of our deferred tax balances in our provisional estimate	5.1	184.0		12.7
Tax expense reflected for other aspects of 2017 Tax Act	11.0
Deferred tax liabilities	695.9	$ 989.6		695.9		$ 989.6
Payment for Transition Toll Tax				85.0
Deferred Tax Liabilities, Other	150.0
Foreign tax authority
Income Tax Contingency [Line Items]
Income tax payment, including penalties and interest	$ 60.0			$ 60.0
Foreign earnings in the form of cash and cash equivalents | 2017 Tax Act
Income Tax Contingency [Line Items]
Transition toll tax repatriation tax rate		15.50%				15.50%
Other foreign earnings | 2017 Tax Act
Income Tax Contingency [Line Items]
Transition toll tax repatriation tax rate		8.00%				8.00%
Accounting Standards Update 2016-16 | Deferred tax asset
Income Tax Contingency [Line Items]
Cumulative effect of new accounting principle							$ 2,000.0
Accounting Standards Update 2016-16 | Deferred tax liability
Income Tax Contingency [Line Items]
Cumulative effect of new accounting principle							1,500.0
Accounting Standards Update 2016-16 | Retained earnings
Income Tax Contingency [Line Items]
Cumulative effect of new accounting principle							$ 500.0

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