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Location of Gains and Losses on Derivative Financial Instruments Designated as Cash Flow Hedging Instruments (Detail) - Cash Flow Hedging - Designated as Hedging Instrument - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Derivative Instruments, Gain (Loss) |  |
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) | $ 3.6 | $ (4.5)
Interest Rate Swaps and Forwards |  |
Derivative Instruments, Gain (Loss) |  |
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) | (0.2) | 0.0
Foreign Exchange Contracts |  |
Derivative Instruments, Gain (Loss) |  |
Gain (Loss) Recognized in OCI on Derivatives (Effective Portion) | $ 3.8 | $ (4.5)

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- Definition The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period. + 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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