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Derivative Instruments and Hedging Activities (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016
Foreign Exchange Contract [Member] |  |
Derivative instrument, terms | The terms of our forward foreign exchange contracts are generally less than 90 days. |
Foreign Exchange Contract [Member] | Fair Value Hedge [Member] | Designated as Hedging Instrument [Member] |  |
Derivative instrument, fair value, net | $ 0.9 | $ (1.1)
Foreign Exchange Contract [Member] | Foreign Exchange Risk of Intercompany Borrowing and Investment Activities [Member] | Fair Value Hedge [Member] | Designated as Hedging Instrument [Member] |  |
Derivative instrument, notional amount | 92.8 | 99.0
Foreign Exchange Contract [Member] | Foreign Exchange Risk of Revenue and Expenses Denominated in Different Currencies [Member] | Fair Value Hedge [Member] | Designated as Hedging Instrument [Member] |  |
Derivative instrument, notional amount | 136.3 | 94.0
Interest Rate Swap [Member] |  |
Derivative instrument, notional amount | $ 1,250.0 | $ 1,250.0

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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 Description of the relevant terms of the derivative. Includes the type of instrument, risk being hedged, notional amount, counterparty, inception date, maturity date, relevant interest rates, strike price, cap price, and floor price. + References No definition available. + Details
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13495-108611 + Details
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- Details
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