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Derivative Instruments (Details Textual) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Derivatives, Fair Value [Line Items] |  |  |  |
Gain/Loss on fair value of foreign currency forward contracts |  | $ (113.0) | $ 49.8 | $ (1.8)
Range of durations of foreign currency forward contracts | 12 months | 21 months |  |
Gain on treasury rate lock settlement |  | $ (42.7) | (92.5) | 6.5
Net gains (losses) of other income (expense) related to foreign currency forward contracts |  | 4.5 | 29.2 | 23.8
Designated as Hedging Instrument |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Aggregate notional amount | $ 2,198.7 | 2,198.7 | 871.7 |
Not Designated as Hedging Instrument |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Aggregate notional amount | $ 564.9 | $ 564.9 | $ 902.1 |
Interest rate lock |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Gain on treasury rate lock settlement |  |  |  | 8.5
Interest rate lock | Designated as Hedging Instrument |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Aggregate notional amount |  |  |  | 1,100.0
Interest rate swap | Designated as Hedging Instrument |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Aggregate notional amount |  |  |  | $ 675.0
4.05% Senior Notes due 2025 |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Interest rate on senior notes | 4.05% | 4.05% |  | 4.05%
5.20% Senior Notes due 2045 |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Interest rate on senior notes | 5.20% | 5.20% |  | 5.20%
2.90% Senior Notes due 2020 |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Interest rate on senior notes | 2.90% | 2.90% |  | 2.90%
Minimum |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Range of durations of foreign currency forward contracts |  | 1 month | 1 month |
Maximum |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Range of durations of foreign currency forward contracts |  | 21 months | 18 months |
Short-term derivative |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |
Gain/Loss on fair value of foreign currency forward contracts |  | $ (98.5) |  |

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- Definition Aggregate notional amount specified by the derivative(s). Expressed as an absolute value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Definition Contractual interest rate for funds borrowed, under the debt agreement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.22(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives not designated as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 + Details
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- Definition Amount after tax, before reclassification adjustments of other comprehensive income (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 55 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=84158357&loc=d3e1436-108581 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Amount of net unrealized gain (loss) related to the change in fair value of foreign currency exchange rate derivatives designated as cash flow hedging instruments. Recorded in accumulated other comprehensive income to the extent that the cash flow hedge is determined to be effective. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 + Details
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