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Derivative Instruments (Details) $ in Millions, ₩ in Billions | 3 Months Ended | 6 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2018 KRW (₩) | Jun. 30, 2018 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2018 USD ($) | Dec. 31, 2018 USD ($) | Sep. 30, 2018
Derivatives [Line Items] |  |  |  |  |  |  |  |
Gain/Loss on fair value of foreign currency forward contracts | $ 6.3 | $ (27.3) |  |  | $ 6.3 |  | $ (27.3) |
Gains (losses) on net investment hedges | 11.7 |  |  | $ 0.0 | 25.7 | $ 0.0 |  |
Net gains (losses) of other income (expense) related to foreign currency forward contracts | (0.9) |  |  | 5.2 | $ (3.9) | 0.4 |  |
Minimum |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Range of durations of foreign currency forward contracts |  |  |  |  | 1 month |  | 1 month |
Maximum |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Range of durations of foreign currency forward contracts |  |  |  |  | 18 months |  | 12 months |
Not designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 934.4 | 735.1 |  |  | $ 934.4 |  | $ 735.1 |
Other current assets | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Derivative asset, fair value | 81.8 | 65.8 |  |  | 81.8 |  | 65.8 |
Other current assets | Not designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Derivative asset, fair value | 6.4 | 1.1 |  |  | 6.4 |  | 1.1 |
Accrued expenses and other | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Derivative liability, fair value | 5.5 | 6.9 |  |  | 5.5 |  | 6.9 |
Accrued expenses and other | Not designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Derivative liability, fair value | 4.3 | 3.2 |  |  | 4.3 |  | 3.2 |
Other long-term liabilities | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Derivative liability, fair value | 2.2 | 0.0 |  |  | 2.2 |  | 0.0 |
Foreign exchange contract | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 2,402.3 | 2,239.1 |  |  | 2,402.3 |  | 2,239.1 |
Interest rate swap | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 675.0 |  |  |  | $ 675.0 |  |  |
Net Investment Hedging |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Remaining duration of Net Investment Hedges |  |  |  |  | 4 months |  |  |
Unrealized gain (loss) on net investment hedges in AOCI |  |  |  |  | $ 19.6 |  | 3.8 |
Derivative qualifying as net investment hedge, excluded component | 9.6 | 7.3 |  |  | 9.6 |  | 7.3 |
Gains (losses) on net investment hedges | 11.6 |  |  | 0.0 | 23.4 | 0.0 |  |
Gains (losses) on net investment hedge, excluded component | 2.3 |  |  | 0.0 | 6.7 | 0.0 |  |
Revenue | Cash flows, revenue | Foreign exchange contract |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Gain (loss) on reclassification of cash flow hedges, effective portion | 29.8 |  |  | (10.4) | 44.6 | (43.3) |  |
Gain (loss) recognized in net income, excluded component | 3.7 |  |  | 7.9 | 7.4 | 7.0 |  |
Operating expense | Cash flows, operating expenses | Foreign exchange contract |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Gain (loss) on reclassification of cash flow hedges, effective portion | (0.7) |  |  | (0.4) | (1.2) | 0.9 |  |
Gain (loss) recognized in net income, excluded component | (0.3) |  |  | (0.1) | (1.2) | (0.4) |  |
Other income (expense) | Net Investment Hedging |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Gain (loss) recognized in net income, excluded component | 2.2 |  |  | $ 0.0 | 4.4 | $ 0.0 |  |
Euro | Foreign exchange contract | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 2,111.3 | 1,701.4 |  |  | 2,111.3 |  | 1,701.4 |
British pound | Foreign exchange contract | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 117.2 | 215.3 |  |  | 117.2 |  | 215.3 |
Swiss franc | Foreign exchange contract | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 69.7 | 131.4 |  |  | 69.7 |  | 131.4 |
Japan, Yen | Foreign exchange contract | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | 56.0 | 98.8 |  |  | 56.0 |  | 98.8 |
Canadian dollar | Foreign exchange contract | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Aggregate notional amount | $ 48.1 | 92.2 |  |  | $ 48.1 |  | 92.2 |
2.900% Senior Notes due 2020 |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Senior Notes interest rate | 2.90% |  |  |  | 2.90% |  |  |
2.900% Senior Notes due 2020 | Interest rate swap | Other long-term liabilities | Designated as hedging instrument |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Derivative liability, fair value | $ 5.5 | 14.5 |  |  | $ 5.5 |  | $ 14.5 |
Samsung Bioepis |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Percentage of stake in entity |  |  |  |  |  |  |  | 5.00%
Equity Method Investment, Ownership Percentage | 49.90% |  |  |  | 49.90% |  |  |
Payments to acquire additional investment in equity method investment |  | $ 676.6 | ₩ 759.5 |  |  |  |  |
Short-term derivative |  |  |  |  |  |  |  |
Derivatives [Line Items] |  |  |  |  |  |  |  |
Range of durations of foreign currency forward contracts |  |  |  |  | 12 months |  |  |
Gain/Loss on fair value of foreign currency forward contracts | $ 9.8 |  |  |  | $ 9.8 |  |  |

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