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Income Taxes (Details Textual) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Tax Credit Carryforward [Line Items] |  |  |
Statutory rate | 35.00% | 35.00% | 35.00%
Income tax benefit (expense) | $ 2,458.7 | $ 1,237.3 | $ 1,161.6
Net impairment on certain tax assets | 48.8 |  |
Income Taxes (Textual) |  |  |
Total deferred charges and prepaid taxes | 617.7 | 989.8 |
Unrecognized tax benefit | 64.3 | 26.9 | 15.7
Net interest expense | 4.8 | 9.1 | $ 3.1
Unrecognized Tax Benefits, Interest on Income Taxes Accrued | $ 16.1 | $ 25.2 |
2017 Tax Act |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Statutory rate | 21.00% |  |
Income tax benefit (expense) | $ 1,173.6 |  |
Accrued income tax liability under the Transition Toll Tax | 989.6 |  |
Accrued income tax liability under the Transition Toll Tax, current | 78.3 |  |
Income tax expense (benefit) | 184.0 |  |
Foreign Tax Authority [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Notice of assessment of corporate withholding tax including penalties and interest | 60.0 |  |
General Business | Domestic Country |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Operating Loss Carryforwards | 1.4 |  |
Tax Credit Carryforward, Amount | 1.3 |  |
General Business | State and Local Jurisdiction |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Deferred Tax Assets, Operating Loss Carryforwards, State and Local | 19.3 |  |
General Business | Foreign Tax Authority [Member] |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Operating Loss Carryforwards | 2,100.0 |  |
Research | State and Local Jurisdiction |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Tax Credit Carryforward, Amount | 129.7 |  |
Prepaid taxes |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Net impairment on certain tax assets | 142.6 |  |
Deferred Tax Asset |  |  |
Income Taxes (Textual) |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | 500.0 |  |
Retained Earnings |  |  |
Income Taxes (Textual) |  |  |
Cumulative Effect of New Accounting Principle in Period of Adoption | $ 500.0 |  |
Earnings in the form of cash and cash equivalents | 2017 Tax Act |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Transition Toll Tax repatriation tax rate | 15.50% |  |
Other Foreign Earnings | 2017 Tax Act |  |  |
Tax Credit Carryforward [Line Items] |  |  |
Transition Toll Tax repatriation tax rate | 8.00% |  |

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- Definition Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences and carryforwards, classified as noncurrent. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e31917-109318 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32537-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84176650&loc=d3e31931-109318 + Details
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