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Derivative Contracts - Additional Information (Details) - Foreign Exchange Contracts - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Not Designated as Hedging Instrument |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Purchase of US and foreign exchange | $ 1,257.3 | $ 751.6
Collateral provided to counterparties as security for the Company's net liability position | 2.3 | 0.6
Not Designated as Hedging Instrument | Derivative At Fair Value |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Purchase of US and foreign exchange | 496.5 | 577.7
Not Designated as Hedging Instrument | Liabilities Under Derivative Contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Purchase of US and foreign exchange | 760.8 | 173.9
Designated as Hedging Instrument |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Collateral provided to counterparties as security for the Company's net liability position | 0.0 | 0.0
Designated as Hedging Instrument | Derivative At Fair Value |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Purchase of US and foreign exchange | 0.0 | 60.6
Designated as Hedging Instrument | Liabilities Under Derivative Contracts |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Purchase of US and foreign exchange | 94.3 | 0.0
Change In Fair Value Of Derivatives | Not Designated as Hedging Instrument |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain (loss) to net income from derivative instruments | (31.8) | 27.7
Net change from current period hedged transactions | Designated as Hedging Instrument |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain (loss) on foreign currency fair value hedge derivatives | (2.1) | 3.0
General, administrative and corporate expenses | Designated as Hedging Instrument |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Gain (loss) on foreign currency fair value hedge derivatives | $ (1.2) | $ 4.4

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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 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 realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CC -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109998890-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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- Definition Amount of gain (loss) from the increase (decrease) in fair value of foreign currency derivatives and nonderivative instruments designated as fair value hedging instruments which were recognized in earnings, net of offsets by the gain (loss) on the hedged item to the extent that the fair value hedge was determined to be effective. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
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