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Derivative Contracts - Fair Value of Derivative Instruments (Details) - Foreign Exchange Contracts - USD ($) $ in Millions | Dec. 31, 2018 | Dec. 31, 2017
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Not Designated as Hedging Instrument |  |
Derivatives, Fair Value [Line Items] |  |
Notional Amount | $ 1,257.3 | $ 751.6
Cash collateral | 2.3 | 0.6
Not Designated as Hedging Instrument | Derivatives at Fair Value |  |
Derivatives, Fair Value [Line Items] |  |
Notional Amount | 496.5 | 577.7
Fair Value | 14.6 | 5.0
Not Designated as Hedging Instrument | Liabilities Under Derivative Contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional Amount | 760.8 | 173.9
Fair Value | (13.9) | (1.0)
Designated as Hedging Instrument |  |
Derivatives, Fair Value [Line Items] |  |
Cash collateral | 0.0 | 0.0
Designated as Hedging Instrument | Derivatives at Fair Value |  |
Derivatives, Fair Value [Line Items] |  |
Notional Amount | 0.0 | 60.6
Fair Value | 0.0 | 1.4
Designated as Hedging Instrument | Liabilities Under Derivative Contracts |  |
Derivatives, Fair Value [Line Items] |  |
Notional Amount | 94.3 | 0.0
Fair Value | $ (1.2) | $ 0.0

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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 The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624258-113959 + Details
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- Definition Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -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 + 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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- Details
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