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Income Taxes (Details Textual) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2018 | Dec. 31, 2017 | Mar. 31, 2017 | Dec. 31, 2017 | Jan. 01, 2018
Income Tax Contingency [Line Items] |  |  |  |  |
Statutory rate | 21.00% |  | 35.00% |  |
Income tax expense (benefit) | $ 322.5 |  | $ 239.2 |  |
2017 Tax Act |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Statutory rate | 21.00% |  |  | 35.00% |
Income tax expense (benefit) |  | $ 1,200.0 |  |  |
Deferred tax liabilities | $ 989.6 |  |  |  |
Remeasurement of our deferred tax balances in our provisional estimate |  | $ 184.0 |  |  |
Current deferred tax liabilities | 85.0 |  |  |  |
Foreign tax authority |  |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |  |
Income tax payment, including penalties and interest | $ 65.0 |  |  |  |
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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