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Income Taxes (Details Textual) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Tax Credit Carryforward [Line Items] |  |  |  |
Deferred tax assets, other |  | $ 103.7 | $ 38.9 |
Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Percent |  | (4.50%) | (1.90%) | (11.10%)
Statutory rate |  | 21.00% | 21.00% | 35.00%
Income tax benefit (expense) |  | $ 1,158.0 | $ 1,425.6 | $ 2,458.7
Income Taxes Paid |  | 87.0 |  |
Deferred tax liabilities, temporary differences, purchase accounting, foreign subsidiaries |  | 1,500.0 |  |
GILTI |  | (1,381.6) | (544.6) |
Net impairment on certain tax assets | $ 48.8 |  |  | 48.8
Decrease in Unrecognized Tax Benefits is Reasonably Possible |  | 75.0 |  |
Income Taxes (Textual) |  |  |  |
Total deferred charges and prepaid taxes |  | 243.8 | 239.2 |
Unrecognized tax benefit | 64.3 | 122.7 | 109.1 | 64.3
Net interest expense |  | 4.7 | 2.2 | 4.8
Unrecognized Tax Benefits, Interest on Income Taxes Accrued |  | 20.0 | $ 13.8 |
2017 Tax Act |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Statutory rate |  |  | 21.00% |
Income tax benefit (expense) |  |  |  | 1,200.0
Transition toll tax liabilities | 989.6 | 697.0 |  | 989.6
Income tax expense (benefit) | 184.0 |  | $ 12.7 |
Reduction in deferred tax liability, undistributed foreign earnings |  |  | 34.6 |
GILTI |  |  | 135.8 |
Other tax expense (benefit) |  |  | $ 11.0 |
General Business | Domestic Country |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Operating Loss Carryforwards |  | 0.7 |  |
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 |  | 4.6 |  |
General Business | Foreign Tax Authority |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Operating Loss Carryforwards |  | 1,773.8 |  |
Research | State and Local Jurisdiction |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Tax Credit Carryforward, Amount |  | 133.8 |  |
Prepaid taxes |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Net impairment on certain tax assets | $ 142.6 |  |  | $ 142.6
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% |  |  | 15.50%
Other Foreign Earnings | 2017 Tax Act |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Transition Toll Tax repatriation tax rate | 8.00% |  |  | 8.00%
ZINBRYTA |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Unrecorded tax benefit |  |  |  | $ 93.8
Minimum |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Residual U.S. tax liability on reversal of deferred tax liabilities on foreign subsidiaries purchase accounting |  | 300.0 |  |
Maximum |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Residual U.S. tax liability on reversal of deferred tax liabilities on foreign subsidiaries purchase accounting |  | 400.0 |  |
Denmark Manufacturing Operations |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Tax expense on disposal group |  | 68.9 |  |
Intellectual Property |  |  |  |
Tax Credit Carryforward [Line Items] |  |  |  |
Deferred Tax Liabilities, Other |  | 603.3 |  |
Deferred tax assets, other |  | $ 754.1 |  |

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