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Derivative Contracts - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016 | Dec. 31, 2016 | May 09, 2016
Goldman Sachs International |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount |  |  |  |  |  | $ 256.3
Foreign Exchange Contracts | Not Designated as Hedging Instruments |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Cash collateral provided | $ 0.6 |  | $ 0.6 |  | $ 0.0 |
Derivative notional amount | 760.2 |  | 760.2 |  | 665.6 |
Foreign Exchange Contracts | Not Designated as Hedging Instruments | Change in Fair Value of Derivatives |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | 4.5 | $ 0.6 | 25.2 | $ (3.7) |  |
Foreign Exchange Contracts | Designated as Hedging Instrument |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Cash collateral provided | 0.0 |  | 0.0 |  | 2.2 |
Foreign Exchange Contracts | Designated as Hedging Instrument | General and Administrative Expense |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Foreign exchange contract settlement | 1.2 | (3.1) | 2.4 | (5.6) |  |
Foreign Exchange Contracts | Designated as Hedging Instrument | Net change from current period hedged transactions |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Net unrealized gain (loss) | (0.4) | 3.1 | 3.3 | (1.9) |  |
Foreign Exchange Contracts | Derivatives at Fair Value | Not Designated as Hedging Instruments |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 521.5 |  | 521.5 |  | 240.2 |
Foreign Exchange Contracts | Derivatives at Fair Value | Designated as Hedging Instrument |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 27.3 |  | 27.3 |  | 0.0 |
Foreign Exchange Contracts | Liabilities under Derivative Contracts | Designated as Hedging Instrument |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative notional amount | 0.0 |  | 0.0 |  | $ 108.6 |
Interest Rate Swaps | Not Designated as Hedging Instruments | Change in Fair Value of Derivatives |  |  |  |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |  |  |  |
Derivative instruments not designated as hedging instruments, gain (loss), net | $ 0.0 | $ 0.0 | $ 0.0 | $ (3.3) |  |

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=84234895&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 The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying 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 (c) -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 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624177-113959 + 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/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 + Details
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